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[-[[caption-width-right:341:[[TruthInTelevision Carlos II "The Hexed" of Spain]]. Most people have family trees. This guy had a [[TangledFamilyTree family tumbleweed]]. Yes, that ''is'' his tongue poking vertically out of his mouth, and yes his lower jaw ''really did'' jut out that far, and yes his nose ''really was'' that messed up. Also, this is a ''flattering'' portrait.]]-]

->''"Madness and greatness are two sides of the same coin. Every time a new Targaryen is born, the gods toss that coin into the air and the world holds its breath to see how it will land."''
-->-- '''Barristan the Bold''', ''Literature/ASongOfIceAndFire''

Nearly every family of a decent size has at least one relative who's a little... strange. Maybe it's Great-Aunt Enid and her collection of carefully mounted cat skeletons (no one knows where she gets them--they just appear), or second cousin Dolf's extensive research library on famous serial killers, complete with memorabilia he buys off of eBay at outrageous prices. (Those [[MonsterClown clown paintings]] he adores are ''particularly'' creepy.)

This isn't much of a problem, usually, as long as one is careful not to get cornered by them at family reunions. But, what happens when your family are [[RoyalBlood hereditary rulers]] of some kind?

Kings, Emperors, High Priests, whatever you want to call it, the point is you have power. Power that belongs to your family, and your family only. Power that somehow meets Crazy. Due to random chance or, sometimes, [[HuntingAccident not-even-remotely-random]], [[TheEvilPrince deliberate action]], [[Literature/HarryPotter Great-Aunt Enid]] or second-cousin Dolf will end up with the royal prerogatives.

[[TheCaligula What follows is either a reign of grotesque excess, blood, and terror]], or some other form of epically [[AdiposeRex bad king]] or [[GodSaveUsFromTheQueen queen]]. Rarely, you'll actually get somebody [[CrazyEnoughToWork so bonkers]] and [[TheMadnessPlace out there]], [[BunnyEarsLawyer they actually]] [[TheWonka work well]] enough for their... little quirks (they're just ''paintings'', for crying out loud!) to be ignorable. Eventually, however, our [[NoodleIncident "At Least Painting the Throne-Room Puce and Yellow Worked"]] King Dolf or [[SerialKiller "Perhaps We Should Have Looked Into Those Cats More"]] Queen Enid will leave the throne (or be made to leave)... That should be the end of this outbreak of eccentricity, right?

Not necessarily. In fact, not even probably. Potentially dangerous insanity in the ruling line rarely appears in a single, isolated case when it comes to fiction. Nope. Chances are the whole family line is just as affected somehow, which means that sooner or later--probably sooner--along will come Queen Enid II and King Dolf III both or either of whom is painfully, obviously off their rocker enough for people to openly comment... And, the whole thing will start up all over again.

This may continue for a good many decades or even centuries, with each new generation crossing its fingers that they get one of the "good" rulers from the line and not one of the "iffy" bunch. If you are unfortunate enough to get stuck with one of the blood-drenched loonies, one common solution is to go find someone else from the [[RoyalBlood same family]] who didn't get hit with the AxCrazy stick and put ''them'' on the throne instead of poor Enid or Dolf before revolution breaks out. This is where disgraced half-brothers, exiled princes/princesses and unknown sons/daughters come into play. Unless something permanent is done about the family problem, however, this is most likely just a temporary solution. Give it a generation or three of this side-branch inheriting, and it's back to our regular Queen Enid "Tree-Whisperer (and Agricultural Reformer)" IV and King Dolf "Utterly Insane" VI programming.

In fiction there are several common reasons why a royal family might be prone to madness.

* '''Genetics:''' It's InTheBlood in the completely literal, biological and strictly genetic sense. Often, that means [[RoyalInbreeding excessive inbreeding]], sometimes ''very'' excessive. The initial problem maybe wasn't inbreeding, but some genetic damage caused by an outside source that then becomes intensified and cemented into the royal line after the fact either through deliberate inbreeding or the sheer bad luck of not understanding biology when selecting mates. In any case, the family just has a crazy streak that's now inbuilt, and you're not getting rid of it unless your society is advanced enough to have genetic engineering (or a magical equivalent thereof) to deal with the problem. Or, becomes egalitarian enough for the high nobility to stop marrying each other so much. That last bit ought to help. Eventually.
** [[LamarckWasRight Moral Lamarckism]] is the classical, magical version. The moral failings of your forebears express themselves in a taint on your own soul or karmic bank balance, like a kind of spiritual gene. Functionally, there isn't much difference.
* '''[[{{Curse}} Family Curse]]:''' Arguably, this is worse than a crappy genetic surprise. Someone, or something, has cursed the royal line... somehow and for whatever reason (most likely revenge). This can easily be a lot nastier to deal with than the problem of bad physical or moral genes, because even if you're careful about avoiding the inbreeding and taking care to select mates for brains, upstanding habits and/or governing skills, the curse really ''doesn't'' care. It may even spread out to people who marry into the royal line and cause them to go mad, even though they're only family by marriage, and not by blood. It also means that you might not solve the problem by just picking a new family to rule over you--they're also likely to get swatted by the curse just as soon as they take power if the thing was either badly worded or specifically made to target those who rule a particular place, rather than just "the family of the one who wronged me". Obviously, to fix this you need to figure out who or what cursed the royal line with what words and why they did it, and then work out how to deal with the mess by whatever means necessary. You could try jumping straight to a parliamentary system to see how the curse deals with having hundreds of "rulers", but you'd better hope it just doesn't spread out to cover them all, or it will make your old problem seem ''laughably'' trivial by comparison.
** One variant of this is a spiritual or moral imbalance brought on by upsetting the planetary or universal equilibrium or law in some way. This works just like a curse, but is the result of natural processes, rather than deliberate, magical malice. This lack of motive can make it harder to detect or uncover.
* '''Cultural:''' The madness is the product of nurture, not nature; which means turning to exiled princes will be fine, at least for the first generation. If people don't change the culture that produced the madness, it will return, however. Possible reasons include:
** The family has just become too used to being pampered and in power over generations, and each successive one has become a little more [[DeadlyDecadentCourt backstabby, corrupt and decadent]] until ''finally'' people start to notice the extent of what has become a huge problem.
** The culture actually ''expects'' its rulers to be [[NeurodiversityIsSupernatural "divinely touched"]] and requires the king or high priest to be at least a little crazy, particularly in theocracies with a MadOracle tradition or another culture with a particularly notable flavour of the DivineRightOfKings idea behind them -- say a line of [[GodEmperor God Emperors]] where rampant megalomania and other quirks are considered just part and parcel of the RoyaltySuperPower package. Not being weird enough might even disqualify you, so you'd better [[ObfuscatingInsanity learn to be nuts]] at the very least. [[BecomingTheMask Comes with risks attached]], however.
** The culture itself is so hard on its rulers that not being [[PragmaticVillainy paranoid and vicious]] means your reign will be measured in months... if you're lucky. In this case, you only look insane to cultures or classes outside your own; within your own palace, [[ProperlyParanoid madness]] is just a [[HadToBeSharp survival strategy]].
** The very way the royal kids are raised becomes severely detrimental to their sanity. Bring them up to specifically become [[ShelteredAristocrat sheltered]], [[EntitledBastard entitled]], [[MoralMyopia morally myopic]], [[LackOfEmpathy empathy-free]] {{Royal Brat}}s and [[TheCaligula Caligulas]] are almost ''inevitably'' what you'll get when they hit majority. Unless they just become reclusive shut-ins who need helpers to do anything, including sneeze. Be it by accident or design, the whole palace has not done anybody any favours.
* '''Environmental:''' Some X-factor specific to the royal family's home location, diet, or environment is mucking things up.
** Heavy metal poisoning, especially lead. (If you're looking for others to shake things up, however; antimony, mercury and arsenic are places to look: they've also had effects.) Seriously; it's a fashion at the moment for forensic archaeologists to imply this as the cause of most of the [[TruthInTelevision real world cases]] of mad monarchs 1500-1815, the source primarily being lead makeup. There were a few reasons for this: lead makes for an easily applied and very white pigment... which aristocrats loved to whiten their skin with to emphasis how little outside work they had to undertake, as well as not to look sweaty or smell so bad (lead pigments also can act to some extent as deodorants). These same aristocrats stopped using makeup from about 1815-1920 for fashion and decency reasons (moral decency, that is); not coincidentally, the incidence of insanity among them dropped, although they weren't entirely clear on why at the time). Although lead in the booze and water (more from the lead used in distilling equipment and pipework than the relatively negligible amounts leached from the crystal glasses) has also been implicated.[[note]]More recently, the higher crime rates in the West and particularly the US 1960-1990 have been attributed to lead poisoning, from leaded gasoline and lead paint. "Lead is bad news" holds for everyone, evidently.[[/note]]
*** There's also a fact that for most of the Classical Antiquity and Middle Ages the lead acetate was known as "sugar of lead" and thought to be a great sweetener: it's cheap, easy to produce and much sweeter than the other alternatives. In was widely used in cider-, perry- and winemaking, and given that for much of the period the preference was for very sweet, syrupy concoctions, it exposed the drinkers to far worse doses of lead than any lead plumbing could.
*** Until the trade with India really picked up at the height of the Roman Republic, and cane sugar started to be imported, about the only sweeteners known in the Europe were honey and must — aka "boiled-up fruit juice or pressings" (see also [[https://fr.m.wikipedia.org/wiki/Vin_cuit_(Suisse) Swiss vin cuit]], a direct, northern descendant similar to apple butter and [[https://fr.m.wikipedia.org/wiki/Vin_cuit_(France) French vin cuit]], a direct southern descendant which is a concentrated wine). The juice of the sweet, ripe grapes famous around the Meditetranean is rich in glucose, and boiling the water off a lot concentrated the sugar; first into the syrupy'' defrutum'', and then into the molasses-like ''sapa''. Given the Romans penchant for lead utensils at every stage, one shouldn't be surprised that they widely used lead-soldered, lead-lined or just plain lead cauldrons to do so, which exposed a lot of lead to the acidic grape juice, leading to formation of the aforementioned lead acetate — as well as lead malate, lead ascorbate and other lead salts that naturally went right into the syrup. In fact, the lead acetate probably got its common name, "sugar of lead", because someone tasted the whitish crystals that formed on the rim of their defrutum-making pot.
*** In East Asian, and especially Chinese, history, the main culprit for royal/imperial madness was not lead but mercury. For complicated reasons, the Chinese alchemists in particular insisted that mercury and its ore, cinnabar, were not only harmless, but key ingredients in any health tonic or elixir of immortality. Naturally, Chinese emperors were all about immortality, and so many an emperor was prescribed the elixirs. You read that right; Chinese emperors willingly ate or drank mercury ''to achieve immortality''. What's more, the alchemists were so sure that mercury was the key to eternal life that they did this for centuries, if not millenia. The first emperor recorded to have gone cuckoo-bird after too much "immortality elixir" was the ''first'' emperor, UsefulNotes/QinShihuangdi, who started off a suspicious but fundamentally sound monarch but ended up completely paranoid after years of "treatment" with mercury-containing "medicine." He was also the first emperor to die from it, after he took pills containing ''pure mercury'' in 220 BCE. Again, [[{{Irony}} he did this as a step to achieving eternal life]]. \\
Undeterred, the alchemists simply concocted new mercury-containing potions, peddling them to subsequent emperors, and hand-waving away the obvious ill effects. One doctor told the Emperor Xuānzong of Tang (reigned 846-859 CE, and generally considered to be the last good Tang emperor) that the [[SideEffectsInclude litany of ill effects he was suffering]]--all of which modern medicine recognizes as symptoms of acute mercury poisoning--were signs that the medicine was working. Xuānzong also died of too much "immortality elixir" after (again) going from a suspicious but capable monarch to a paranoid wreck over the course of several years of treatment. Qin Shihuang and Xuānzong weren't the only ones; practically every Chinese dynasty has at least one monarch who trusted the peddlers of immortality potions too much, and got a nasty case of quicksilver poisoning for his trouble.
** Disease. Specifically, something like syphilis; it's an STD, so it would get passed around the court, it causes madness if untreated, and the first generally effective treatment wasn't discovered until the 20th century: [[http://en.wikipedia.org/wiki/Arsphenamine Salvarsan]]. This links back to the heavy-metal poisoning: the common treatment before Salvarsan was ''mercury'', and while that sometimes worked it also ran the risk of driving the patient a different kind of mad through mercury poisoning. Fun fact: syphilis can (and has) inserted its DNA into the human genome, just for that extra InTheBlood sparkle you might be looking for.
** A mysterious food, drink, drug or influential thing or place reserved for royal use, only (the crown, palace or throne are good ones to go for), with side effects. If a place or thing rather than a drink or drug, expect some form of radiation specifically attached to it of ether molecular or magical origin. If combining with magic, expect... a Curse and see further up this list.
* '''They're Just Nuts:''' Anything and everything not covered by the above. Sometimes, mental illness just turns up both uninvited and unwanted. Rulers are no exception.

Whatever the reason, your rulers are bonkers, at least as far as objective outside observers are concerned.

Note that royal/imperial insanity is TruthInTelevision often enough that it can be a bit frightening.

TheCaligula is a singular example of this trope, leaving out the familial tendencies, although they arguably applied to him too. InTheBlood doesn't apply only to royals, but is one of the many reasons why a royal family can have recurring madness problems.



[[folder:Anime & Manga]]
* A borderline case in ''Manga/DragonBall Z'': although [[BigBad Frieza]] is the most well-known member of his family, others are shown, and for the most part, they're just as [[ProperlyParanoid crazy]] and [[AxCrazy evil]] as he is. Fan theories tend to attribute this trope to why they're essentially LawfulEvil.
* ''Manga/OnePiece'' has the World Nobles, otherwise known as the ''Tenryuubito'' (or "Celestial Dragons"). In particular, we meet a family of three World Nobles, St. Rosward and his children, St. Charlos and St. Shalulia. Their only claim to influence is being the direct descendants of kings who founded the One Piece-verse's World Government. However, that claim allows them to perform atrocities ranging from shooting people for having the gall to speak to them directly to randomly naming women on the street as the newest additions to their long lines of wives (and sending the ones they're tired of back to the common folk) with absolutely no fear of retribution as the government will sic a Marine Admiral, complete with fleet, on anybody who dares defy them. Not that Luffy cared.
** Hell, they're even above monarchs of the countries that ''encompass'' the World Government, yet they do no actual governing at all. Lesser nobles of such countries with monarchs of a similar mindset are willing to do anything to impress them in hopes that they will use their authority to ''up their status as nobles''. One notable instance of this was [[spoiler:Goa Kingdom, the place where Luffy and Sabo were born, and the place where they and Ace were raised]].
* In ''Manga/MagiLabyrinthOfMagic'' we have the ''[[BigScrewedUpFamily Kou Royal Family]]'', integrated by a ''[[AxCrazy variety]] [[EvilMatriarch of]] [[ManipulativeBastard members]] [[BeautyIsBad of]] [[EvilRedhead all]] [[BloodKnight flavors]]''! Their internal conflicts are so alike to those of a soap opera, a ''deranged'' soap opera.
* In ''Anime/CodeGeass'', the Royal Family of the [[TheEmpire Holy Empire]] of Britannia are all pretty messed up for the most part, ranging from [[TheChessmaster Lelouch and Schneizel]], to [[LadyofWar Cornelia]], to Clovis, who wipes out a whole section of dilapidated city to cover up his mistakes. And that's not even talking about [[BigBad Emperor Charles]], his [[spoiler: EvilMatriarch partner Marrianne, who is NotQuiteDead, and his ''insane'' brother V.V.]]. Luckily there's some hope. [[RebelliousPrincess Euphemia]] is a generally sweet girl, and so is her younger sister, [[IllGirl Nunnally]]. Crown Prince Odysseus is also pretty decent, though that may be because he doesn't really do much of anything (not to mention being [[DumbIsGood probably the least intelligent of the family]]). Unfortunately this series likes to [[KillTheCutie kill the kind ones]].
* An interesting variant: the heir presumptive of the Holy Kingdom of Saillune in ''LightNovel/{{Slayers}}'', Prince Phillionel, while somewhat of a LeeroyJenkins-like lunatic with a passion for [[BadassNormal physical fights]], is probably ''the'' sanest and respectable member of the family and a stellar runner of the country; his younger daughter [[ThePollyanna Amelia]] has most of his traits. The rest of the family is filled with [[DirtyCoward Dirty Cowards]] who will do anything to move up a spot for the throne, with no concern for others -- both of Phil's younger brothers, Christopher and Randionel, and his nephew, Alfred, have attempted to murder him. Alfred in particular contracts one (two in the anime) [[AlwaysChaoticEvil Mazoku]] to both take out Phil and take Saillune for himself while letting Christopher (his father) take the blame. [[spoiler:In the novels, Christopher himself [[OffingTheOffspring kills Alfred]] to prevent any more damage, and nearly commits suicide himself]].
** [[spoiler:Among the craziest is Amelia's older sister, Gracia, otherwise known as Naga the Serpent. She runs off after Phil's wife is murdered, which is NOT helped by how ''she'' found her mom dead and [[BloodyMurder bloodily killed the assassin]]. She then spent years traveling alone (and with Lina) in an attempt to obtain treasure, learn about the world (sort of), [[HardDrinkingPartyGirl drink]], and gain fame without much effort ([[UnknownRival which definitely doesn't work in her favor, especially when she's traveling with Lina]]). While she is willing to help others, she is like Lina insofar as she does it for her own gain. In the novels, she keeps in contact with Phil, but in other media it seems that she hasn't made contact in years, which disconcerts Amelia.]]
* ''LightNovel/SaiunkokuMonogatari''. Where to even begin? The previous emperor of Saiunkoku deliberately pitted his sons against each other, and then exiled his former favorite, the most competent of the lot. Of the remaining five princes, all but the youngest were killed fighting each other in a SuccessionCrisis that nearly destroyed the country. The UnFavorite [[UnexpectedSuccessor youngest]] son Ryuuki became the heir. Ryuuki was none too keen on this and [[ObfuscatingStupidity feigned incompetence]] and [[BiTheWay spread rumors about his sexuality]] to make himself unpopular and get out of producing an heir. Ironically, avoiding the temptations of power and recognizing his own insufficient preparation for the throne made him the ClosestThingWeGot to a stable, responsible Emperor. Ryuuki starts to act like a real ruler after his advisors find him a consort capable of acting as a [[StayInTheKitchen privy councillor]]. Oh, and that exiled prince? Turns out he's [[HiddenBackupPrince not so exiled after all...]]
** And that's not even getting into the seven ''other'' families that make up the ruling class of Saimono. To give a sense of how screwed up ''they'' are, the Kou family is currently being lead by Kurou, the youngest of three ''living'' brothers, because Shouka and Reishin each tossed the clan leadership like a hot potato as soon as it fell to them. Kurou just hasn't got anyone else to palm it off on, so he gets stuck herding crazy assassination-happy cats.
* ''Anime/VampireGame'' is all about one princess's dealings with her own extended Royally Screwed-up family, wherein IncestIsRelative is the ''least'' screwed-up thing one can encounter, not to mention the Chimeras and of course Royal espionage. Oh, and there's a vampire who wants to kill her, too. This is mostly a ''comedy''.
* From the second season of ''Manga/BlackButler'', [[AxCrazy Alois]] [[CreepyChild Trancy]].
* In ''Anime/SamuraiPizzaCats'', Princess Vi is a selfish, spoiled brat who exiles people to Prisoner Island at the drop of a hat, her mother considers firing a rocket launcher at her daughter an appropriate family greeting, and Emperor Fred... to say he's got a few screws loose would imply he's got any screws left.
* The Zabi family from ''Anime/MobileSuitGundam'' put the Screwed Up in BigScrewedUpFamily. Patriarch and Sovereign Degwin is a WellIntentionedExtremist who seeks to TakeOverTheWorld in the name of his ideology. [[TheEvilPrince Eldest son Gihren]] is a [[TheSociopath psychopathic]] [[TheSocialDarwinist Social Darwinist]] who could not care less about ideology and just wants to [[DespotismJustifiesTheMeans increase his own power whatever the cost]]. Second son Dozle is more or less normal, but turns into an AxCrazy [[TheBerserker berserker]] when turned loose on the battlefield. Daughter Kycilia is a cold-blooded amoral schemer who wants the throne for herself, and doesn't [[WeHaveReserves give a damn about human life]]. The only exceptions seem to be youngest son Garma, and Dozle's daughter, Mineva, who [[spoiler:is raised away from the family, after all of their respective deaths]].
* The three Vance sisters from ''Anime/QueensBlade'' are so messed up that, if it weren't for the fact that their father seems to be a fairly sane, stable sort, one would think the gods were justified in dethroning their family's ancestors as the former rulers of the known world and replacing the hereditary nobility with the eponymous tourney, which seems tailor-made to avoid the negative effects that this can have on the political arena.
** Firstly, the sisters as a whole are part of an [[BrotherSisterIncest incestuous]] lesbian LoveTriangle, where eldest daughter Claudette has a crush on youngest daughter Elina that goes unrequited (except in the ''Hide & Seek'' continuity) because Elina is instead obsessively in love with the middle daughter, Leina. Leina herself is only AmbiguouslyGay, but is stable enough that if she is a lesbian, her attraction is to a woman who is ''not'' one of her sisters. Also, all three of them have ''serious'' mommy issues due to their MissingMom -- Claudette actually gets a ''double'' whammy of this, as her mother died before her father married the woman who gave birth to Leina and Elina, and then she died as well.
** Claudette has serious issues with her family due to the fact that she's an illegitimate daughter and so not allowed to officially inherit the family estates, despite being the most formidable fighter. She does love her sisters, but at the same time she hates them, and she also feels torn between love & loyalty and hate for her father. [[spoiler: In ''Rebellion'', with a little magical coaxing from the Swamp Witch, her negative feelings turn her into a full-blown EvilOverlord, thanks in part to Leina giving her the throne of Queen.]]
** Leina is technically the most stable of the sisters, but still suffers from [[HeroicSelfDeprecation severe inferiority issues]] that make her feel unfit to be the heir to the Vance family name and induce her to try and literally run away from her responsibilities.
** Elina, finally, is the most unquestionably screwed up of the sisters. A SpoiledBrat who regards all others as beneath her notice and tortured one of her servants to the point she becomes ''one of the series' {{Big Bad}}s'' just for the hell of it, which she did ''as a child'', she has a complete LackOfEmpathy and is also an unabashed incestuous PsychoLesbian, who in the first anime episode is seen vindictively talking about how she'll make Leina's future husband suffer for having the audacity to marry her beloved sister.

[[folder:Card Games]]
* Ironically, this pops up in ''TabletopGames/LegendOfTheFiveRings''. Odd for two reasons: One, the new family line had two generations before being wiped out in their entirety. And two, none of them seemed to be genetically crazy, the first emperor went nuts after being kidnapped and tainted, the next because he had way too much magical power, and the third because his sister died, and the evil of the world showed up and asked if he could join the royal court.
* ''TabletopGame/YuGiOh'''s [[http://yugioh.wikia.com/wiki/Brron,_Mad_King_of_Dark_World Brron, Mad King of Dark World]] certainly gives off this impression. If the name doesn't tip you off, the SlasherSmile and the fact that he's apparently chained up should. Strangely enough, it seems that the others are ''aware'' of this; not only are Brron's stats and abilities quite average, but [[AllThereInTheManual the second Master Guide]] claims him to be more of [[AuthorityInNameOnly a ceremonial figurehead]] than anything, while the generals and other warlords do all the actual governing.

[[folder:Comic Books]]
* Franchise/MarvelUniverse character of antiquity [[ComicBook/SubMariner Namor the Sub-Mariner]] is both an example and a subversion. By all accounts, he rules the kingdom of Atlantis relatively well. However, he is also provably crazy: his unique Atlantean/Human physiology means that he requires both air and water to function properly, and if he goes too long without one or the other, his body chemistry drives him towards excessive rage and dangerous short-sightedness; a very dangerous thing indeed in someone strong enough to fight the Hulk to a standstill.
* Also of Marvel, ComicBook/{{Magneto}} and his offspring formed a ComicBook/HouseOfM in the miniseries of the same name, but in a subversion (aversion?), the royal family seemed pretty well-balanced. In the [[ComicBook/UltimateMarvel Ultimate line]], however, the same 'royal family' is... Well, let's just say they've got ''problems''. General explanation? Big Daddy M's crazy-genes, plus power-induced madness.
* The Neramani Royal Family of [[Franchise/XMen the Shi'ar Empire]]. Being at the head of a star-conquering alien empire is bad enough, but two of their individual members are [[TheCaligula insane sociopaths]]: Deathbird [[CainAndAbel killed her sister]], [[SelfMadeOrphan as well as her parents]], though its somewhat attributed to her atavistic mutation. Her younger brother D'Ken is a GalacticConquerer who threatened the whole universe, while [[EverythingIsBetterWithPrincesses their Lilandra]], on other hand, is quite [[TheHighQueen a stable ruler]], but has tendency to get dethroned frequently. It gets much worse when Deathbird [[UnholyMatrimony marries]] [[AxCrazy the equally-deranged Vulcan]], bringing even more crazy to the family. By the [[ComicBook/WarOfKings Kree-Shi'ar War]]'s end, most royal members are dead including Lilandra, D'Ken and Vulcan while Deathbird goes missing. The Shi'ar elect [[MyCountryRightOrWrong Gladiator]], the family's bodyguard to be their Emperor instead. The siblings' uncle, who is the only surviving Neramin relative, declines the throne stating their people would riot if another Neramani was their ruler.
* In the ComicBook/XWingSeries, royalty of the planet Eiattu interbreed and use technology to keep the line "pure" of the ills afflicting the common folk. But nature abhors a vacuum. Plourr Illo, revealed as the last confirmed survivor of the main royal family after the other nobles had a bloody revolution (her story was loosely based off of the legend of Anastasia), tells the other characters why the man rumored to be her brother (a new kind of revolutionary, this time of the common people) can't be him.
-->"All those years of dipping from the same genetic pool caused a wrinkle, a flaw in an otherwise normal family line. We set out to keep ourselves above the common man and found ourselves with a thing from the deepest pit of the Sith."
** Well, she also knows it's not him because on the night her family was killed, her father managed to get the two of them out and her brother started screaming for the revolutionaries to come and find her and slit her throat so he could be Emperor. [[http://asylums.insanejournal.com/scans_daily/728104.html So she killed him]].
* The Holy Grail in ''ComicBook/{{Preacher}}'' is an organization that has kept the bloodline of UsefulNotes/{{Jesus}} pure for around two millennia. Unfortunately, they did this via BrotherSisterIncest, generation after generation, resulting in [[UncannyValley sickly, skinny people with eyes like an anime character]]. As Herr Starr puts it, they're lucky the current (mentally retarded) descendant doesn't have antennae.

[[folder:Fan Fiction]]
* The ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' fanfiction, ''Fanfic/MaternalInstinctMLP'' has the royal family of the Changeling Kingdom, the House of Roachanov. Although Changeling culture is primarily based off UsefulNotes/ImperialJapan, the royal family has a reputation of intermarriage amongst its members that, throughout generations has led to many physical and mental disabilities and illnesses much more similar to those of old European royalty. Queen Chrysalis appears to have dodged most of these ailments, but her daughter and heir, Crown Princess Pupa is both heavily mentally and physically disabled. Pupa, at the time of the fanfiction, is approximately the same age as the Cutie Mark Crusaders, yet she can neither walk or talk, and is treated as virtually an infant and carried around as one by her careers. She is comparable to King Charles II of Spain and Feodor I of Russia. As one commentator remarked, ''"the Changeling royalty is essentially a tour of all the screwed up monarchies of Europe."'', again ironic as the culture is primarily Japanese.
* [[http://www.fanfiction.net/s/2138275/1/ Let Them Fade]] is a terrific Franchise/HarryPotter fic exploring, in the form of a conversation between Snape and an adult Hermione, the results of long-term inbreeding among Purebloods, the wizarding world's analogue to royal inbreeding: "For every Pureblood child in my generation, I have calculated or deduced the existence of five stillbirths or miscarriages." She also points out an increasing number of Squibs and prevalence of learning disorders among the surviving Pureblood children, and calculates that the Death Eater war hastened the fatal genetic bottleneck by 200 years, because it killed off a substantial chunk of the remaining gene pool. [[spoiler:She covers these findings up in her official Ministry report but tells Snape in private. That way he can discreetly spread the word to affected families but there won't be any coercive breeding laws based on her discovery.]]
** In ''[[http://www.fanfiction.net/s/5651585/3/Wizards-are-stupid Wizards are stupid]]'', a collection of one-shots dedicated to demonstrating the stupidity of Potterverse wizards, the third chapter "Incest is bad" is dedicated to Draco Malfoy's birth: the first Draco was a circus freak [[BodyHorror (with three arms, fourteen fingers on the arms, three testicles and no penis, two mouths (one on the side of the face, the other on the neck), among other things),]] quickly killed and incinerated, and there were three other freaks, stillborns, or miscarriages before we got the Draco we met in the series. It's openly attributed to inbreeding, with Lucius and Narcissa being presented as first cousins on the Black side of the family, and the author gleefully pointed out many alternatives.
* In the setting of ''FanFic/SonicXDarkChaos'', the Emirate of Mecca is ruled by the House of Ishmael. How utterly corrupt and screwed up is it? The [[TheCaligula Prophet Muhammad]] (who happens to be a completely insane dictator who tried to irrigate fields with blood) is considered to be ''one of the better members''. The family is the primary reason for the Emirate being a nightmarish totalitarian theocracy. According to WordOfGod, it was explicitly based on the real life Saudi royal family.

* Invoked with Ruprecht in ''Film/DirtyRottenScoundrels''. Lawrence has been posing as a prince to con money out of rich ladies. Whenever an heiress gets too close to his con, he gets Freddie to play a mentally disturbed brother to scare her off.
* In ''Film/TheHobbit'', this is the case for the dwarven King Thrór and his grandson Thorin. Apparently, it was Thrór's excessive greed that brought the dragon Smaug to Erebor. Later, Thorin succumbs to dragon sickness, claiming the wealth of Erebor is greater then any life, suspecting the Company of stealing the [[MacGuffin Arkenstone]] and almost throwing Bilbo from the ramparts when he finds out he took the Arkenstone to the elves and men. He refuses to help the Iron Hill dwarves outside when they're fighting a massive army of orcs and goblins, leading to a WhatTheHellHero from Dwalin. Thorin eventually realises how dangerous his greed is and leaves Erebor to help fight against Azog's army. [[spoiler:He is fatally wounded in a MutualKill with Azog, but before Thorin dies he makes his peace with Bilbo.]] Subverted with Thráin, Thorin's father, who ''did'' go mad, but only after years of grief, isolation, and torture.
* The Abrasax clan from ''Film/JupiterAscending''; even the best of them--arguably [[spoiler:Kalique]], the only one whose endgame doesn't seem to necessitate Jupiter's death--has no qualms committing genocide for the sake of immortality.
* The Prentiss family in ''Film/TheManchurianCandidate'' (known in the novel as Iselin). The novel alludes pretty frankly to [[spoiler:incest between Eleanor and her father Tyler]], and relates with equal candor at least one instance of same between [[spoiler:Eleanor and her son Raymond. While he's under mind control, no less.]] All three are driven, passionate patriots working at high levels of office -- Tyler was a diplomat, Eleanor is a Senator and Raymond is a Representative running for Vice President. Over the course of his campaign it is revealed that his mother [[spoiler:has been involved for many years in a conspiracy which began with the Congressional Medal of Honor and ends with an assassination attempt on the president-elect and, ultimately, the deaths of both Raymond and Eleanor]].

* The ''Literature/{{Hurog}}'' family tends to sadism and jerkishness in the male line. More precisely, everyone who lives in castle Hurog is affected in some way, some suffer inexplicable psychological issues, others are suicidal. The fact that the castle was built by an EvilSorcerer, who turned his bastard son into the child in PoweredByAForsakenChild, by turning him into a kind of GeniusLoci that is enslaved, and compelled to serve the head of the family, is probably responsible for that -- not so much the genes, as the fact that all heirs of the title live in this castle. Evil is not good for your sanity, and owning a slave whose very ''soul'' is bound to obey tends to weaken the moral backbone of those who didn't have much decency to begin with. Oreg, the above-mentioned slave, wrote a curse/prophesy on the wall some couples of centuries ago, but that, if at all, only contributed to the paranoia, as he did is as reaction to something very cruel his then master did.
* Creator/LoisMcMasterBujold's ''Literature/VorkosiganSaga'' has the Vorbarra Imperial line. Thanks to inbreeding and genetic damage caused by environmental factors, some of the Vorbarra rulers have been... problematic:
** Mad Emperor Yuri killed off most of his own family and then got dismembered and scalped by his own nobles, led by his brother in law[=/=]cousin.
** Yuri's brother in law[=/=]cousin[=/=]successor Ezar was a relativly sane [[TheChessmaster Chessmaster]], but was also [[TheUnfettered ruthlessly amoral]] beyond belief. The man signed off on a pointlessly aggressive war ''he knew Barrayar would lose'' to topple his political enemies and [[OffingTheOffspring kill his own son]].
** Ezar's son Serg was a twisted sadist who probably would have destroyed the Imperium if he'd been allowed to take the throne. Ezar [[OffingTheOffspring killed him]] in a UriahGambit (too bad about the grunts).
** Serg's son Gregor inherited the throne at age five when Ezar died, and, remarkably, grew up sane and stable thanks mostly to his adoptive parents, [[{{Cincinnatus}} Aral Vorkosigan]] and [[WarriorTherapist Cordelia Naismith Vorkosigan]]. But Gregor became so paranoid about the genetic insanity in his family line that he refused to consider marrying anyone even ''distantly'' related to him. Since that equated to all the nobility on the planet, there was no clear line of succession[[note]](of the four with the closest blood right, two would cause mass revolts if they even looked at the camp stool whilst the other two would sooner eat plasma arcs than take the job)[[/note]], and Gregor's death would have caused a massive and probably final civil war...this posed a bit of a problem.
*** Fortunately Barrayar has recently gotten a handle on genetic engineering, eased up on the social stratification, and annexed another planet with its own unrelated set of merchant nobility (one of whom Gregor eventually married), so that nasty strain of ''[[CanisLatinicus nutjobbus maximus]]'' is likely to be cleansed from the line in the future. Much to the relief of Gregor, Aral, Cordelia, and every planet anywhere near Barrayar.
* Cursed royalty also appears in Bujold's ''Literature/{{Chalion}}'' books (she seems to like the trope).
** The main curse of madness/misfortune/sterility/whatever would make things most difficult in ''Literature/TheCurseOfChalion'' is particularly nasty, in that it automatically spreads to anyone who marries into the family, making it completely impossible to eradicate without, as it turns out, ''direct intervention from the gods''. The unlucky king Orico tried to short-circuit it by [[spoiler:getting his wife, Sara, pregnant by his chancellor, because any child of theirs would not be part of the cursed royal bloodline]]. It didn't work because [[spoiler:Sara was barren and also the chancellor was evil and his brother was an evil whackjob]], but one gets the impression it was a clingy curse that would have come down on ''whoever'' inherited the throne, as well anyone around them who could potentially have finagled a way out. Thus, it took a miracle in the end.
** And then there's that strange familial wolf-madness thing in ''Literature/TheHallowedHunt'', too. [[spoiler:Revealed not to be madness, but an ancient shamanistic tradition that creates powerful animal spirits linked to certain rulers; the protagonist's dad just had the bad luck to pick a sacrificial animal that was rabid and bit him before it died, and the poor protagonist wound up convinced his own wolf-spirit would do the same to him.]]
* Present in Creator/DavidEddings' ''Literature/TheBelgariad'', in the form of the royal line of Cthol Murgos, the Urgas family, with its hereditary insanity. In sequel series ''The Mallorean'', the eventual successor to the throne is more or less sane, which makes sense, given that he's [[spoiler:not actually the son of the crazy late king, but instead the product of a brief affair between one of the king's wives and a foreign diplomat.]] That's one effective way to get the crazy genes out of the royal line.
** Made even more effective by the traditional method of ensuring easy succession: whoever gets the throne has every other potential claimant assassinated. ''Legally''. Maybe the Murgos have had problems like this before...
*** TruthInTelevision -- the early Ottoman Empire tried to cut down on wars of succession by having all male relatives of a newly crowned sultan put to death. Predictably this only ''increased'' the number of succession wars, as every potential claimant to the throne knew that upon the death of the old sultan he had to either win the crown or die. Urgit's quote of "It was either the throne or the block." in ''King of the Murgos'' is drawn straight from history.
** The various Tolnedran imperial dynasties tended towards this as well. Typically the first few emperors of a dynasty would be clever, competent men, but after several generations of inbreeding the line eventually devolved into rulers who were insane, imbeciles, or both. And then subverted by the Borunes, who by their contractual obligations have to marry Dryads. Introducing exogamy into the family line every generation must help. Of course, female members of the Borune family are Dryads also (and exclusively Dryads, [[OneGenderRace there's no such thing as a female half-Dryad]])...
* In Creator/TeresaEdgerton's ''Literature/TheGrailAndTheRing'', it is revealed that Mochdreff has been politically unstable for centuries largely due to the land having been cursed due to the sins of its last ruling prince. He committed an action so terrible that every single member of his family changed their names and refused to take up the sovereignty -- although only people like Dame Ceinwen remember even that much of the story, and nobody remembers the specifics. Ever since, there have been Lords of Mochdreff rather than rulers styling themselves princes, until finally, due to the lack of a clear heir to the previous Lord, Prince Tryffin was appointed Royal Governor and took it upon himself to try to clean up the matter once and for all by getting to the bottom of the curse.
* In the ''Literature/SwordOfTruth'' series, the Rahl family line, for several generations, have been warmongering psychopaths. [[spoiler:The protagonist]] is, depending on the reader, either an exception or adhering to the rule.
* ''Literature/{{Everworld}}'' provides a variant: due to the royal tradition of BrotherSisterIncest, the last twelve Pharaohs of Everworld Egypt have all been mentally disabled and unable to rule in anything but name. This, coupled with the fact that the Egyptian gods are basically [[spoiler:so obsessed with ritual that they've become willingly comatose]], made the country weak and unstable enough for [[LadyLand the Amazons]] to take over.
* In P.C. Hodgell's ''Literature/ChroniclesOfTheKencyrath'', the house of Knorth, from which the ruling Highlords come, has what appears to be an inherited tendency toward madness. Torisen, the current Highlord, is terrified of what lurks in his bloodlines, and of becoming like his father and grandfather. Inbreeding and deliberate breeding for Shanir (magical) traits is probably responsible.
* ''Literature/{{Redwall}}'''s Marlfoxes. The mother Silth is a raving maniac, her youngest is a sneak who deliberately feeds her mother's paranoia in order to weasel (or fox?) her way into power, and the oldest six offspring are just plain nasty to various degrees.
* The Kingdom of Delain, in ''Literature/TheEyesOfTheDragon'' by Creator/StephenKing, suffers from this problem every now and again. Particular mention is made of Mad King Alain, who was truly a raving and unstable lunatic but did his people the favor of dying quickly -- he decided to go outside and play games on the lawn during a raging thunderstorm (lunatic, remember?) and got struck by lightning.
* The Argaven kings of Karhide in Creator/UrsulaKLeGuin's ''Literature/TheLeftHandOfDarkness'' are described as congenitally mad. This seems to be accepted as part of the nature of kings on Gethen.
* The page quote comes from ''Literature/ASongOfIceAndFire'', in which the royal Targaryen line is said to be blessed with greatness as much as it is cursed with madness, in part due to centuries of inbreeding to keep the "[[RoyaltySuperpower Blood of Old Valyria]]" pure. It started with the first Targaryen king, who was a great man but unfortunately married and had children with both of his sisters (a family tradition); from there on out it's been a crapshoot. The line has produced many able warriors, statesmen, and scholars as well as a rogue's gallery of tyrants and psychopaths. Some Targaryens begin quite noble and lose their grip on sanity as they age, such as King Aerys II -- by the end of his reign, he was known as King Aerys the Mad, and in the end his excesses sparked a revolt that toppled the dynasty. Daenerys, the only POV character with Targaryen blood ([[EpilepticTrees so far as we know]]), seems more sound of mind than her relatives, but is a bit delusional and idealistic, and would do well to take the advice of those around her. The books give us only one normal Targaryen [[spoiler:(two if you count Jon Snow)]] -- Maester Aemon, as even the much liked Rhaegar was bipolar and had delusions of grandeur.
** The Lannisters seem to be heading the inbred-madness route, too: [[spoiler: King Joffrey and his siblings Myrcella and Tommen]] are the product of BrotherSisterIncest between [[spoiler:Queen Cersei (married to King Robert, whom she hates) and her twin brother Jaime. Jaime and Cersei's parents were first cousins]]. Cersei is a paranoid schemer who eventually engineers her own downfall, and [[spoiler:Joffrey,]] her son was sadistic and unstable and had to be put down by [[spoiler:Littlefinger and the Tyrells]]. Hopefully averted with Prince Tommen and Princess Myrcella, who are both perfectly sweet children... for now.
*** Well, the incest might be a factor (and, those who believe Stannis will no doubt jump on that explanation). However, [[RoyalBrat Joffrey]] really didn't have a chance: his mother both spoiled and smothered him as well as refused to let anybody else educate him... while neglecting such things as mathematics, ethics, psychology, and ''reading''. His father, although not exactly abusive, was both distant and neglectful. Anybody else who could have stepped in to discipline or direct him were either chased off (Maesters) or never spotted the problem until far too late (Grandfather, Father-by-blood and Uncle).
** The Targaryen madness is, in truth, highly overrated.
-->• Aegon I -- Perfectly normal,\\
• his son Aenys I -- Fairly normal, if a bit indecisive,\\
• his half-brother Maegor I -- Psychopathic murderer,\\
• his nephew Jaehaerys I -- Best king Westeros ever had,\\
• his grandson Viserys I -- Aside from not clearing up his line of succession, quite normal,\\
• his son Aegon II -- Paranoid, but for good reason, however lustful and unpleasant\\
• his nephew Aegon III -- Depression, but stemming from watching his mother be devoured by a dragon rather than genetics,\\
• his son Daeron I -- Became king far too young but not actually crazy,\\
• his brother Baelor I -- Religious fanatic but nonetheless loved,\\
• his uncle Viserys II -- Kept his nephews from imploding the realm during their reigns, but died before he could finish the job as king himself\\
• his son Aegon IV -- Obese, corrupt, and horribly ineffectual,\\
• his son Daeron II -- Second best king Westeros ever had,\\
• his son Aerys I -- Obsessed with books to the exclusion of all else, including having children,\\
• his brother Maekar I -- As stern, harsh, and unyielding as his great-great-grandson Stannis and even more unpopular but again not crazy,\\
• his son Aegon V -- Sane aside from maybe the Summerhall incident and well-known for his kindness to the smallfolk,\\
• his son Jaehaerys II -- Often considered weak due to his poor health and short reign but thought well of by anyone who actually knew him, managed to do some good things during his brief time [[note]]End the Blackfyre Rebellions and reconcile the Great Houses [[/note]]\\
• and his son Aerys II -- Psychopathic pyromaniac.
** That's only three crazy kings, two borderline crazy kings, and one horribly incompetent one out of the seventeen monarchs. If you want to count the Targaryens who never became kings, only Rhaegal (brother of Aerys I and Maekar), Aerion (brother of Aegon V), and maybe Viserys (brother of Daenerys) were crazy.
*** CrowningMomentOfAwesome for whoever took the time to figure out this family line.
** The Targaryen madness really seems to be prominent in the more recent generations. Aerys II was the craziest of the lot, both of his sons had problems, his daughter isn't that much better (although whether she's actually mad [[FlameBait is a highly controversial debate topic)]] [[spoiler:and his possible surviving grandson also has issues (which actually convinces Tyrion that he really is a Targaryen), although his other grandson (who is unaware of his true lineage) is fine other than being pretty emo at times]].
*** It's not clear at all that Rhaegar inherited any of Aerys II's madness [[spoiler:especially if his kidnapping of Lyanna Stark was not a kidnapping at all]]. Rhaegar however was pretty emo at times [[spoiler:much like his second son]], which only got worse as he became more obsessed with the prophecy of the "Prince who was Promised".
** It's unknown how many Targaryens were passed over for the throne due to either mental defects or poor physical health. The insanity problem became prevalent enough that the councils would try to skip over the crazy or sickly Targaryen in the line of succession in favor of [[SpareToTheThrone a more stable younger son or nephew]]. And in later generations, a significant number were born with moderate to severe mental defects, or "feeble-witted".[[note]]This applied to Aerion Blackfyre's daughter and at least several more children, but because they were never seriously considered in the line of succession, little was recorded about them.[[/note]] Even their physical health was eventually effected, with several being intellectually and emotionally normal but possessing such [[IllGirl fragile immune systems]] that they suffered from numerous ailments and died young. Stillbirths and cradle deaths were ''very'' common, even when [[CrapsackWorld considering the time period]].[[note]]Dany's mother, Queen Rhaella, had no less than two stillbirths, three miscarriages, and three infant sons who were born alive but so sickly that none of them lived more than a year.[[/note]]
* In the ''Literature/InheritanceCycle'', there once was a King by the name of Palancar who tried to wage war numerous times with the Elves, even though every invasion was a hopeless crusade. Eventually his nobles rebelled against him to end the madness and had him exiled into a valley that later inherited his name. The Protagonist and his cousin, and the village they grew up in, descended from Palancar. Paolini so far has acted like that's at least somewhat of a ''good'' thing. Then again, he's also trying to convince us that the one who's really Royally Screwed-up is Galby.
* Fiona Patton's [[Literature/TalesOfTheBranionRealm Branion]] series is set in a fantasy Britain where the gods take an active interest in their followers. The royal family, whose head is called the Aristok, is literally touched by the gods -- the sovereign is the avatar of the Living Flame, a deity/demon/primordial critter which is a sort of symbiotic parasite. This makes the Aristok something of a cross between a hereditary Christ-figure and the real British system of the monarch being head of the church. Not only does the Aristok have [[DivineRightOfKings divine right]], she can prove it. Unfortunately, being the physical sacred vessel-on-earth of a ''fire god'' is bad for your health. Out of forty-one monarchs, sixteen have died young, been assassinated, or committed suicide, and many of the rest went insane. Three even converted to a completely different faith, which made for real cognitive dissonance among their followers as well as themselves. Whether this system is a blessing or a curse on the royal family is clearly up in the air.
* The first two of Mervyn Peake's ''Literature/{{Gormenghast}}'' books are, among other things, a long examination of this trope -- the Groan lineage and their staff are a bunch of depressed lunatics, their spirits both crushed and perversely sustained by the castle and its ancient, messed-up rituals. They are a sympathetic bunch though -- the melancholy and bookish Lord [[MeaningfulName Sepulchrave]] and his unloved, {{cloudcuckoolander}} daughter [[TheOphelia Fuchsia]] must surely be among the most tragic literary [[TheWoobie woobies]] of the last century.
* Zigzagged throughout the ''Literature/{{Discworld}}'' novels.
** Historically, the rulers of Ankh-Morpork have tended to be raving psychopaths. This may have been somewhat genetic while the city was a monarchy and rulers' marriages were arranged to maintain the royal blood and survival tended to favor those homicidal enough to keep ahead of the DeadlyDecadentCourt. However, even after the kings were overthrown and replaced by the non-hereditary Patricians, the stress of the job and the absolute power that came with it turned pretty much everyone who held it some flavor of barking mad. The last two Patricians were known as "Mad Lord Snapcase" and "Homicidal Lord Winder". By a stroke of ''incredible'' good fortune the current Patrician, Lord Havelock Vetinari, is not only sane but an utter MagnificentBastard and as insurance, the rightful heir to the line of kings is also hanging around the city, and he's also sane-ish, as he was raised by dwarfs (his adoptive father was in fact a king, but among dwarfs that job corresponds to "mine director" and appears to be elective, not hereditary).
** The old noble houses of Ankh-Morpork, from which the Patricians are usually chosen, certainly haven't done themselves any favors through repeated intermarriage but, as with the royal line, this is implied to have contributed less to their overall unpleasantness than the self-selection towards dimwitted murder-happy prats (because of the military service requirement) and the self-absorption encouraged by privilege.
** ''Discworld/InterestingTimes'' zigzags this with the Agatean Emperor. While his insanity is suggested to have a dash of genetic inbreeding behind it, the book hints (yet ''again'') that ''intentionally'' breeding for paranoia and psychopathy, and then not telling the offspring why cruelty is bad, may have actually played a larger role than how closely related his parents were. Lord Hong, the real BigBad, subverts the trope entirely by simply being a self-made MagnificentBastard without any of Vetinari's redeeming scruples.
** ''Discworld/{{Pyramids}}'' thankfully manages to avoid this, although it is specifically mentioned that the BigBad had intended to wed the protagonist with his aunt in order to keep the royal line [[PureIsNotGood "pure"]].
** Played utterly straight when one book describes the lineage of kings in other Discworld city-states, and cites the last King of Quirm as having been so inbred he repeatedly tried to mate with himself.
* In Creator/JackVance's ''Literature/{{Lyonesse}}'' trilogy, the king of South Ulfland's single son, Prince Quilcy, is feeble-minded and spends his days playing with fanciful doll-houses.
* In the ''[[Literature/TortallUniverse Tortall]]'' books by Creator/TamoraPierce, the Copper Isles royalty tend to have madness crop up now and then, including one Princess Josiane. A character phrases it thus: "There's bad blood in the Copper Isles kings. They birth a mad one every generation. Josiane's uncle is locked in a tower somewhere. It comes from being an island kingdom -- too much inbreeding." It turns out in further novels that it may not be just one per generation...
** Two per generation, as of the Trickster books. The old king who dies and prompts the SuccessionCrisis and his brother who was mentioned as locked in a tower somewhere, and Josiane and Imajane among the old king's kids.
** The Jimajen line might also have bits of this, though we only see two members: Rubinyan, whose only major flaws are an overdeveloped sense of honor and an inability to control his insane wife; and Bronau, who is extremely egotistical and ambitious without much common sense to go with it. Big brother is also ambitious as hell, but much more sensible...
** Emperor Ozorne of Carthak and that cousin of the Tusaine line who starts the Tusaine-Tortall war in the second Song of the Lioness book both count.
** Duke Roger, nephew to King Roald in the Song of the Lioness quartet, wasn't insane to begin with, but coming back from the dead (or not, precisely, if you believe him) certainly screwed with his head.
* In the ''[[{{Nightrunner}} Tamír Trilogy]]'' (''The Bone Doll's Twin'', ''Hidden Warrior'', and ''The Oracle's Queen'') hereditary madness has hit the royal line. What makes this particularly dangerous is that the country's god has declared that only women of that bloodline can become ruler... or else. At the end...[[spoiler: the sanest remaining member of the royal line takes the throne and the madness that caused the whole situation is just never mentioned again, since the epilogue indicates that there were no problems for centuries afterwards.]]
* Averted in the ''Literature/HonorHarrington'' series with the Star Kingdom of Manticore. Aside from being a constitutional monarchy, which limits the potential damage, Manticoran monarchs and heirs apparent are specifically prohibited from marrying members of the aristocracy. Aside from the "keeping in touch with the common folk" goal, it also removes the problems of inbreeding.
** He swiped this from Creator/EEDocSmith's ''Family d'Alembert'' series; under the Stanley Doctrine, nobility ''could'' marry commoners, but royalty was ''required'' to marry a commoner. While this helped, this was not totally successful in keeping loonies from the Imperial Throne (granted, the case of Empress "Mad Stephanie" could have been situational rather than genetic.)
*** In the case of the Stanley Dynasty, it may be as much cultural as genetic. At one point the competent, sane, and decent Emperor William (who is definitely an exception to the run of his ancestors) makes a joke about his and his wife's decision to abdicate at his age 70, so their daughter Edna "won't have to kill us." Edna is horrified by the joke, but her father points out that if he'd been more grasping and determined to hang on to power forever, decent Edna might have turned out different too, because, as he notes, 'like begets like'.
** The author even points out that if the Monarch is really bonkers, Impeachment is in the Constitution, with Parliament choosing the new Monarch from any person in the Kingdom.
*** And before being added to the official line of succession, the Monarch's offspring have to pass a psychological and intelligence evaluation.
** The Andermani Emperors on the other hand are competent but sometimes ''strange'': the first emperor thought he was a reincarnation of Friedrich der Grosse (UsefulNotes/FrederickTheGreat of UsefulNotes/{{Prussia}}). Another was dethroned when he not only talked to his prize rose bush but also tried to make it chancellor.
*** And he was deposed by his own sister, who, while generally considered the best Andermani Emperor ever, had to [[SheIsTheKing legally declare herself a man]], due to their Salic Law succession. May not have been the best decision for her own mental state.
*** It's hinted the reason why they are so successful is that the insanity and the genius go together. After all founding a New Prussian Empire on a Chinese colony world and making it into a regional power does sound pretty nuts. The first Emperor was a rich space pirate who saved the colony from starvation.
** Actually, while she's generally sane, Queen Elizabeth III does have her own set of issues. Her temper, for instance, is usually described as "volcanic".
* The Civil Government of the planet Bellevue in ''Literature/TheGeneral'' series qualifies as both the current governor and his acknowledged heir are borderline clinical paranoids, and becoming less borderline all the time...
** Though, considering the political climate in the Gubierno Civil, the line between clinical paranoia and [[ProperlyParanoid sane, reasonable social caution]] is slim indeed. The ''only'' reasons the POV character isn't a threat to the throne are his incorruptible idealism and his sure knowledge of the disaster that will ensue if he tries to take the throne for himself. Also, while the Cleretts my or my not be insane, they are also competent, if perhaps not excellent, political and military leaders.
** A better example would be Settler Ali ibn'Jamal of the Colony, who is just an old-school psychopath.
* The pureblooded Ancient and Most Noble House of Black from ''Literature/HarryPotter'' has a long history of insanity and inbreeding. Most pureblood wizarding families (with a few exceptions, like the Weasleys, who aren't hostile to mixed or Muggle-born in-laws) have gone this direction in recent decades, as the limited gene pool means they're all increasingly interrelated. Arthur Weasley says at one point that purebloods by the current definition will probably die out within a couple generations, as so many of them are already first cousins and within the incest taboo. Ironically, the Death Eaters probably managed to hasten this extinction quite a bit since many purebloods died in the fighting or were consigned to Azkaban afterwards.
** The Gaunts are even ''more'' messed up and inbred than most purebloods, since Dumbledore mentions that they were the only remaining descendants of Salazar Slytherin and Marvolo was obsessed with the inferiority of other families. Ironically, the worst member of the family is conceived when they finally manage to get some new blood: [[BigBad Lord Voldemort]], the son of Merope Gaunt [[BoomerangBigot and a Muggle]].
* The Raiths in ''Literature/TheDresdenFiles'', the royal family of the [[EmotionEater White Court]] of vampires. The White King [[MoralEventHorizon rapes his female children into supernatural slavery]] and [[OffingTheOffspring kills off his sons]]. His daughter Lara is a MagnificentBastard who lives on the line between SociopathicHero and FriendlyEnemy AntiVillain. The only reason his son Thomas lived to adulthood is by playing the RichIdiotWithNoDayJob card for everything it's worth. The only one who doesn't appear to be incredibly messed-up is [[spoiler:Inari Raith, who never became a full-on succubus because she [[ThePowerOfLove fell in love]] and Lara helped her get away]].
* In ''Literature/TheSilmarillion'', the first king of the Noldor, Finwë, is a good man, but after his death, the crown goes to his eldest son Fëanor, who was very paranoid before, and became completely crazy (if still very charismatic) when his father was murdered. Once Fëanor is also dead, his son Maedhros should become king...but he averts this trope: knowing how dangerous the Oath he and his brothers have sworn is, he abdicates and lets his uncle rule. It's a wise move: the sons of Fëanor do commit some horrendous acts, and the two eldest eventually become insane, but at least they only rule a fraction of the Noldor.
** The royal family of Númenor also develop into this, as they become more and more jealous of the Elves for their long life, and determined to find a way to live forever. This culminates in the last ruler of Númenor [[RageAgainstTheHeavens basically declaring war on God]] and [[CurbStompBattle losing]] [[WorldSundering horribly]]. Ar-Pharazon wasn't even the rightful King, having usurped the throne by forcing his cousin, the rightful ruler, to marry him.
* Literature/TheBible is chock full of lousy or downright ax crazy evil kings of Israel who choose to snub the God who saved their ancestors from Egypt, so much so that the good kings are the exception.
** And even the good kings still tend to be royally screwed up. Witness David, whose punishment for committing adultery with Bathsheba and [[TheUriahGambit having her husband killed]] was that his first son by her fell ill and died a week later, and the rest of the sons started killing each other for various reasons. David ultimately appoints Solomon as his successor, and even then the succession crisis doesn't end. Solomon was also messed up in his own right on account of his [[LoveRuinsTheRealm harem of foreign wives.]]
* Averted in the ''Literature/HeraldsOfValdemar'' series, in part because Valdemaran law forbids a monarch (or, presumably, heir) from marrying anyone within two degrees of kinship. And the newly-crowned Selenay plays it to the hilt to keep her councilors from forcing her into marriage, too. The requirement that all monarchs must be [[IncorruptiblePurePureness Heralds]] is also very important -- there's nothing saying a Herald can't be a bit nuts (Hi, Lavan and Vanyel!), but at least it's the type of nuts that doesn't result in the abuses seen on the rest of this page.
* King Rodric IV in ''Literature/TheRiftwarCycle''. Hated and abused by his father for being a sickly runt, he proved to be as sick in mind as he was in body. Apart from using openly about how his power would allow him to randomly pick out random people and have them executed for no reason other than he wished to see them die, he squandred much of the tax revenues of The Kingdom Of The Isles on a series of aesthetic public works programs designed merely to make the city of Rillanon look prettier. Worse still, he denied vital military aid to the Western half of his Kingdom, fearing that the soldiers would be used to build an army against him, which helped to drag the first Riftwar out for the better part of a decade.
* Though not quite royalty, the Usher family in Creator/EdgarAllanPoe 's ''Fall of the House of Usher'' fits. An illness that causes madness runs in the family, and it's implied to be due to inbreeding.
* A rather desperate attempt to prevent this touched off the entire plot of A.L. Phillips's Literature/TheQuestOfTheUnaligned. The royal house of the realm of Caederan, instead of being tied to one of the four elemental magics, are tied to all of them as the result of an ancient magical bargain binding the King and Queen to Caederan itself. Unfortunately, this means that if the King and Queen favor one element over the others, this will throw the land itself out of whack. A few decades before the story started, King Kethel and Queen Tathilya became increasingly infatuated with the power of air, which also had the side effect of causing them to become increasingly flighty and absent-minded. As the Balance fell further and further towards wind, the country was wracked by droughts, tornadoes, cyclones, and other catastrophes. When Queen Tathilya became pregnant, the nobles realized that if the new prince was raised in the royal court, he to would become infatuated with air magic. The nobles launched a desperate bid to separate Prince Alaric from the ruahk-controlled Court, and thus begins the plot.
* ''Literature/AgeOfFire'': The Imperial Line of the Lavadome is ''very'' messed up. [[EvilMatriarch Tighila]] kills her own son and frames and exiles her mate's later chosen heirs, before eventually killing him too, all so that her brother [=SiDrakkon=] can become Tyr. When he does, he takes Infamina, his great-niece, as his mate, and ends up nearly bringing the Lavadome to civil war due to his [[TheCaligula refusal to do anything that doesn't satisfy his hedonism]]. This lasts until Infamina's brother [=SiMevolant=] assassinates him, [[BrotherSisterIncest takes Infamina as his own mate (and it's implied they were already having an affair)]], and proceeds to [[spoiler: play TheQuisling to [[GreaterScopeVillain the Wrymmaster's]] forces, letting them take over the Lavadome]], which causes [=RuGaard=] (an adopted member of the Imperial Line) to lead a rebellion to take [=SiMevolant=] down, becoming Tyr himself afterwards.
* Played with in ''Literature/KingdomOfLittleWounds''. Everything that would normally be attributed to RoyalInbreeding or a FamilyCurse is actually caused by an epidemic.
* Royal family of trolls in ''Literature/MaledictionTrilogy'', mostly because of 500 years of inbreeding. The father, king Thibault, is morbidly obese, the queen is conjoined with her sister, the younger son Roland is beautiful but stark raving mad. Only prince Tristan seems to be normal - but he is seriously considering [[SelfMadeOrphan murdering his father]] and brother for the higher good.
* ''Literature/{{Dune}}'':
** House Harkonnens are not really that screwed up from the start. It’s just that [[FeudingFamilies they had a beef with House Atreides a long time ago]]. It’s only when [[TheCaligula Vladimir Harkonnen]] came into the picture, things went worse. His nephews aren’t much better though one character commented that Feyd-Rautha might have become a great hero, if only someone who wasn’t such a monster had raised him.
** It also turns out that Paul and Alia Atreides are [[spoiler:Harkonnens too, thanks to their mother who is Vladimir’s biological daughter]]. Paul is not much of a monster like his grandpa as most of his detractors think; it’s just that he fell in a prescient trap and couldn’t control things such as his rabid followers. His sister is indeed messed up because her mother consumed spice and inherited GeneticMemory of the past Reverend Mothers and all of their ancestors while pregnant. Because of this, she’s called as an Abomination by the Bene Gesserit and they had a good reason to call her that most especially when [[spoiler:she got possessed by her evil grandpa in ''Literature/ChildrenOfDune'']].
** In any case, Bene Gesserit’s plan to control the genes of several noble houses has something to do with this trope. In the past, they made tons of effort to create the Kwisatz Haderach but it produced a lot of failures (e.g. Count Hasimir Fenring). They nearly got it right this time except this Kwisatz Haderach came too early and they ended up paying the price when he became Emperor and unleashed his fanatics throughout the universe.
* ''Literature/AFrozenHeart'' expands on Hans, a major character from ''Disney/{{Frozen}}'', and what his family situation looks like. Short version: it wouldn't be out of place in ''Literature/ASongOfIceAndFire''. Long version: his father is a violent SocialDarwinist dictator who both routinely abuses his wife and sons and encourages the latter to do the same to Hans. He also taxes his subjects into poverty and brutally suppresses any opposition to his regime.

[[folder:Live Action TV]]
* In ''Series/BabylonFive'', the nephew of Emperor Turhan, Cartagia, became the Emperor of the Centauri Republic after his uncle's death. Emperor Cartagia was as bad as any fiction-version of UsefulNotes/{{Caligula}}, and apparently [[TheCaligula modeled after him]].
** Interestingly, the position of Emperor does not seem to be connected to any individual line for more than a few generations; it appears to be totally normal for the Centauri nobles to hand the throne to a new House even though the old imperial house still exists ([[spoiler:Londo rules as Mollari II, as one of his ancestors had held the throne once]]). This presumably means that Cartagia's madness was a relatively rare occurrence in his House -- rather as the Julio-Claudians only had two Emperors who could be called insane (Caligula and Nero), only one of whom (Caligula) was ''totally'' bonkers (Nero, while an awful ruler, was not ''totally'' incompetent).
* ''Series/DoctorWho'': [[Recap/DoctorWhoS28E2ToothAndClaw "Tooth and Claw"]] strongly implies that eventually the British Royal family might become werewolves. However at the time Victoria had already had all her children, and the Doctor is on good terms with UsefulNotes/HMTheQueen, so it was clearly a joke.
* ''Series/GameOfThrones'' implies this is caused by inbreeding in the Targaryen and [[spoiler:Lannister]] family lines, in as little as one generation. The crazy rate is implied to be around 50% (as per the page quote), regardless of how long the inbreeding has been practiced. Technically the [[spoiler: Lannister]] case isn't a single generation; [[spoiler: Jaime and Cersei]] are first generation sibling incest, but their parents were first cousins. And since no particular fuss is made over that fact, it can be assumed that cousin incest is not uncommon in the Lannister family. [[spoiler: Cersei and Jaime]] were far from the first incestuous pairing in the family, but they were probably the straw that broke the camel's back. Furthermore, they're both unpleasant people (though [[spoiler:Jaime]] is [[TheAtoner trying to be less unpleasant]]), and their son Joffrey seems to combine the worst aspects of each. His siblings Myrcella and Tommen, on the other hand, are perfectly reasonable people (though Tommen is an ExtremeDoormat) who [[spoiler:wind up being TooGoodForThisSinfulEarth thanks to Cersei's machinations, leading to the end of their house.]] Furthermore, though not crazy, all of the Lannisters mentioned except Kevan have issues. Tytos had a desire to please that made him a doormat, Tywin sees people as tools for his work, as mentioned above the twins are unpleasant, Tyrion is an alcoholic dwarf with terrible family relations, Lancel is a zealot, and there is one who just smashes beetles while screaming crunk.
* A lot of tension surrounding the SuccessionCrisis in ''Series/{{Merlin|2008}}'' is based on this trope. It's revealed in series three that the Pendragon men have a history of mental illness, one which King Uther ultimately succumbs to after his [[spoiler:arguably AxCrazy illegitimate daughter]] betrays him and takes the throne.
* Invoked in ''Series/TheMusketeers'', when after outwitting some depraved noblemen, Aramis says "Centuries of inbreeding is making the aristocracy (taps the side of head) stupid."
* Referenced in the ''Series/RedDwarf'' episode ''Rimmerworld''. Kryten explains the problem of having an entire society descended from Rimmer [[spoiler:and his clones]] by drawing comparisons with European monarchies of the 19th and 20th centuries. The actual leader of the planet seems to be an example himself.

* The entire [[Myth/ClassicalMythology Greek Pantheon]], in many ways.
* OlderThanDirt: The [[Myth/EgyptianMythology Egyptian Pantheon]] is just as messy.
** Older still: The [[Myth/MesopotamianMythology Mesopotamian Pantheon]].

[[folder:Tabletop Games]]
* From ''TabletopGame/BattleTech'', the Liao dynasty of the Capellan Confederation seemed to produce only two kinds of rulers. [[TheCaligula Batshit insane]] and [[MagnificentBastard batshit evil]]. The non-insane non-sociopath Liaos tended to defect to other nations, neatly removing any descent chance of cleaning the batshit out of that genepool for a long time. Fortunately for the Capellan Confederation, the batshit evil variety tends to serve the needs of the populace; they're seen as evil by other nations that they're screwing over.
** Also, the Steiner dynasty of the Lyran Commonwealth has a genetic predisposition to a few psychological conditions. They never get to the truly batshit level of insanity, but they have been known to do substantial damage to their nation.
** It's applied to each of the five major factions at some point. Perhaps the most notorious version in-universe is Jinjiro Kurita, who ordered his troops to kill 52 million people on a world where his father was killed by a sniper.
* ''TabletopGame/{{Ravenloft}}'' had ''Legacy of the Blood'', describing the relatives of the various {{Big Bad}}s of the domain of dread, as well as options for [=PCs=] to play relatives of them.
* The House of Naelax, rulers of the Great Kingdom of Aerdy in the ''TabletopGame/{{Greyhawk}}'' setting, were commonly viewed as being possessed by demons. [[http://www.canonfire.com/cfhtml/modules.php?name=News&file=article&sid=528 This article]], although written by a fan for his own campaign, is nonetheless a good summary of what the Ivid Overkings were like.
* ''TabletopGame/{{Warhammer}}'' is fond of this trope. During the most decadent period of the Empire's history, it's implied that inbreeding reached epic proportions and led to actual mutations among the nobility. They seem to have straightened things out for the most part by the "present day" though. Thank Sigmar for the [[BurnTheWitch witch hunters]], eh?
** Inverted in the case of Bretonnia though, where it's the ''peasants'' who are inbred and deformed. Some recent anthropological research suggests this may be [[TruthInTelevision Truth in, er, roleplaying games]].
* ''TabletopGame/{{Warhammer 40000}}'' has numerous examples of hereditary planetary rulers who follow this trope -- though [[Literature/CiaphasCain Inquisitor Vail]] would point out that this doesn't happen ''quite'' as often as the stereotypes would have you believe. In worst case scenarios (such as Osric the Loopy, mentioned in passing in ''The Traitor's Hand''), the [[PsychoForHire Officio Assassinorum]] can be dispatched to "tidy up" matters.
** ...actually, that's a lie. In ''worst'' case scenarios, the Royally Screwed-Up ruler is a heavily mutated [[TheCorruption Chaos]]-worshiper who unleashes the LegionsOfHell on the planet they're supposed to be governing. In ''those'' scenarios, [[EarthShatteringKaboom stronger steps are taken]].
** And that's not getting into TheEmperor, [[TrulySingleParent his sons]], [[Literature/HorusHeresy and the tragedy that shattered the galaxy]].
*** Of course, the Emperor was probably the sanest person in the galaxy and up until the Heresy the majority of his sons were perfectly sane as well. (The exceptions being Kurze, a murderous sociopath; Angron, a blood-crazed berserker; Lorgar, a raving zealot; and Alpharius, who had colossal delusions of grandeur. [[MassiveNumberedSiblings So 4/5ths of his kids were perfectly sane.]])
* In the TabletopGame/OldWorldOfDarkness RPG ''TabletopGame/WerewolfTheApocalypse'', many of the ruling tribe, the Silver Fangs, suffered from this--despite the fact that werewolves had to outbreed (werewolf-werewolf matings were lucky if their children were just insane). Of course, interbreeding [[TooDumbToLive with the Habsburg line]] didn't help.
** Somewhat justified in that the Silver Fangs had such an obsession with lineage that they refused to breed with any humans that weren't royal. So they managed to get most all the bad traits of just about everyone in the "Real Life" section below.

* By the end of ''Theatre/{{Electra}}'', Chrysothemis is probably the only member of the royal family who hasn't tried to murder another member in retaliation for a previous murder.

[[folder:Video Games]]
* ''VideoGame/ArmedAndDangerous'' has an interesting case: a magical curse cast on the kingdom of Forge causes one king of the country to be a clever EvilOverlord, and his immediate successor to be a [[TheFool kind-hearted dimwit]], and his successor again to be an EvilOverlord, and so on. In retrospect, it might have been a better idea to make the evil one the idiot.
* ''Franchise/TheElderScrolls''
** The Septim Dynasty of the Third Cyrodiilic Empire, [[FounderOfTheKingdom founded]] by [[GodEmperor Tiber Septim]], had its fair share of crazy. To note:
*** Emperor Pelagius Septim, aka "Pelagius the Mad". He was an AxeCrazy MoodSwinger and very much the shining example of TheCaligula in Tamriellic history. He suffered from extreme weight fluctuations and tried to hang himself at the end of a royal ball. He insisted on his palace [[NeatFreak always being kept clean]] and (perhaps apocryphally) was said to defecate on the floors to keep his servants busy. He would only communicate with the [[LizardFolk Argonian]] ambassador in grunts and squeaks, believing it to be the Argonian language. He'd frequently [[FullFrontalAssault strip naked in public and, toward the end of his life, would attack and bite visitors]]. He was eventually declared unfit to rule and his wife by arranged marriage, Katariah, the [[OurElvesAreBetter Dunmeri]] former Duchess of Vvardenfell, took over as [[RegentForLife Empress Regent]]. However, according to Sheogorath, the [[OurGodsAreDifferent Daedric Prince]] of [[MadGod Madness]], Pelagius may have been seriously screwed up compared to the average person, but was, for a Septim, pretty normal. While history records most of the Septim line as perfectly sane and even austere, this implies that the [[WrittenByTheWinners Imperial propaganda machine]] has done it's job in hiding the family's eccentricities.
*** Pelagius aunt, Potema "the [[RedBaron Wolf Queen]]" of Solitude, wasn't much better. In an attempt to get her son on the Imperial throne, she kicked off the War of the Red Diamond, the bloodiest CivilWar in Tamriellic history. By the end of the war, she had gone completely off the deep end and used {{necromancy}} to bolster her dwindling forces. Ironically, Solitude is suggested to have endured more than its fair share of these kind of rulers in its history.
*** Sanguine is the [[OurGodsAreDifferent Daedric Prince]] of [[FunPersonified Debauchery]] and [[TheHedonist Hedonism]]. According to ''The Imperial Census of Daedra Lords'', "As revelry and drunken stupor fall under this Prince’s influence, he has been a favorite of many Emperors since the first foundation."
** The Black-Briar family of ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'' appear to be of the Environmental and Cultural types, being raised by a corrupt business owner in the WretchedHive of Riften. Hemming is a stuck up brat, Sibbi is a sociopathic killer, and Ingun, the nicest of the bunch, has a strange affinity for alchemy, ''especially'' poisons. [[spoiler:Close attention to dialogue also shows this to be InTheBlood as well, as Hemming will refer to Sibbi and Ingun as both his siblings and ''his children'', and looking at the game files shows that Maven is marked as Sibbi and Ingun's ''grandmother''.]]
* ''Franchise/FireEmblem''. Good lord, ''Fire Emblem''. ''Every freakin' game''. Granted, no more than two games (except 1/11, 2 and 3) take place in any one continuity, but regardless, there is at least one mad ruler per game, or at the very least, mildly evil (''Blazing Blade's'' King Desmond wasn't really mad, just a petty idiot--and Marquess Laus ''wanted'' to rule all of Lycia, but never actually did.) Well, okay, ''[[VideoGame/FireEmblemTellius Radiant Dawn]]'' actually had a bunch of evil senators trying to usurp the empress of Begnion and an EvilChancellor at the side of the new king of Daien...[=FE10=] ''did'' have Naesala, but he turned out to be...compromised.
** ''VideoGame/FireEmblemAwakening'' goes one step further: not only is the main villain the result of a [[spoiler: thousand years long program of eugenistic breeding among plegian royalty meant to create an avatar to a demonic genocidal city-sized dragon]], but this time, [[spoiler: s/he's the protagonist. Kind of.]]: Fire Emblem: by Nintendo, the company known for its [[WhatDoYouMeanItsNotForKids colorful family friendly]] games
** ''Videogame/FireEmblemFates'' . Both royal families of Hoshido and Nohr are dysfunctional. The Nohr family is the more troubled of the two, since their father Garon sired many children with his concubines. The infighting and power struggles killed off most of the half-siblings -- the relatively sane and decent ones are the only ones ''left''. Garon himself was hardened by this [[spoiler:but he's still not to blame for all of the really awful things that happen in the game, since he's a DeadAllAlong puppet of the true BigBad Anankos.]] If Nohr used to be dysfunctional but the infighting stopped after Elise's birth and from there the siblings get along well, Hoshido was the opposite. They used to be a happy family, but everything fell apart after [[spoiler: the Avatar was kidnapped by Nohr and Sumeragi assassinated]]. The two older siblings Ryoma and Hinoka trained themselves too hard, busying themselves to distract themselves from the sadness of losing their father and younger sibling, but distancing themselves from their left younger siblings (namely Takumi and Sakura). This is visible in their supports, that Nohr siblings cleared their inner conflicts well, but the Hoshido siblings... Do not completely clear their problems, even if you A support all of them. If you [[spoiler: sent the younger siblings fight the oldest one in ''Revelation'', this also shows. Xander has special dialogue if you sent Camilla against him, but Ryoma DOES NOT have any special dialogue even if you sent Takumi or Sakura against him. Even more so against their father Sumeragi. Sumeragi only has special dialogue with the Avatar and Ryoma, showing clear signs of ParentalFavoritism.]] The straightest example of an insanely evil royal is [[spoiler:the protagonist's true father Anankos who also happens to be a godlike dragon, but even that's due to a flaw with dragons in the Fire Emblem verse: If they spend too long in their dragon forms without using a [[PowerLimiter dragonstone]] they go insane. Anankos is even worse than the normal insane dragon, because his sane half is still aware of what's going on and ''[[AndIMustScream can't do anything to stop it]]'']]
* The Dresari family in the ''VideoGame/MechWarrior 4'' series appears to suffer from this; it's doubly painful because [[spoiler: the likable player character in the first game pulls a FaceHeelTurn and becomes TheCaligula in one of the expansions]]. Per a previous example, this is not entirely uncommon in the [=BattleTech=] universe.
** Weirdly enough, WordOfGod [[RetCon retcons this]] saying that the latter incident mentioned above is in fact [[spoiler: [[http://www.sarna.net/wiki/Ian_Dresari#Tyrant propaganda]] from the aforementioned Steiner ruling government, whose leader at the time was not above this or numerous other antics reaching to the MoralEventHorizon]].
* Even without that whole [[spoiler:one of them [[HumanSacrifice having to die]] every generation to stop the end of the world]] thing, the Granorg royal family from ''VideoGame/RadiantHistoria'' is pretty messed up. The late king was [[TheCaligula cruel and incompetent]], his wife is ''[[GodSaveUsFromTheQueen worse]]'', the crown prince was executed for disagreeing with them, and the princess is now [[RebelLeader leading]] LaResistance against her stepmother. [[spoiler:And the king's brother is the OmnicidalManiac BigBad.]]
* ''VideoGame/{{Zork}}'': the entire Flathead dynasty, ruling or not, with the sole exception of the last Flathead king, Wurb, and [[spoiler: [[VideoGame/ZorkGrandInquisitor Lucy Flathead]]]].
* Keep marrying relatives in ''VideoGame/CrusaderKings II'' and you are liable to end up here -- the game keeps track of familial connections enough to mark characters down as inbred behind-the-scenes. This trope comes in in that there are two traits you can get just from being inbred -- the inbred-only inbred trait (with a wide range of negative effects) covering mainly the physical sides of this, and the lunatic trait covering TheCaligula side of it. Religions that ''encourages'' incestuous marriages are nice enough to decrease the risk of getting the inbred trait, but only at the cost of making lunatic more likely.
* ''Videogame/BlazBlue'' features the Yayoi family, one of the twelve ruling families of the Duodecim. They rarely show up directly, but they are pretty messed up from what we know. Members of the Yayoi family would [[SuperpowerfulGenetics only have children]] with those who had strong [[{{Magitek}} Ars Magus]] potential. Eventually they [[IncestIsRelative started inbreeding]] due to considering themselves the only ones strong enough. The current heir, [[YamatoNadeshiko Tsubaki]], is not the firstborn child; she's the first one that ''survived''. She's strong and nice, but she's [[GreenEyedMonster not]] [[{{Yandere}} quite]] [[HorribleJudgeOfCharacter right]] and ends up manipulated.

[[folder:Web Comics]]
* Princess Sara in ''[[Webcomic/EightBitTheater 8-Bit Theater]]'' is smart, sexy, and sane enough to fully realize her father is a CloudCuckooLander with genocidal tendencies. Naturally, she doesn't hold much stock in hereditary rule. She's still a rude, shrewish sociopath, though, and engineered her own kidnapping.
** How bad it is: No matter what horrible evils she unleashes on the populace when she comes into power, it will look like a golden age compared to the completely ruinous and unhinged chain of decisions King Steve makes every day, simply because she's not enough of an idiot to be capable of the same levels of casual destruction.
*** It's even worse than that: King Steve boasted a 52% approval rating. He got this by having pollsters ask which would they prefer: Having Steve as their king or taking a sword to the head. 48% of his subjects chose execution (And received it).
* The Masters Royal Family of ''[[http://chesspiece.smackjeeves.com Chess Piece]]'' are said to be cursed. Luckily, it skipped a generation. Unluckily, the current Prince has seriously planned on ''taking over the world'' since he was ''four''.
* Nearly every [[TheClan clan]] in ''WebComic/{{Drowtales}}'' could fit into this, but the Sharen are the most screwed up. Matricide, starting a civil war, and subjecting one's entire clan as well as any female summoner to demonic Tainting, is a good start for proving a case of mental imbalance. Zhor claims that [[spoiler:Snadhya'rune]] is truly insane (not just evil or ruthless, but ''insane''), and Diva knew it.
** The Sarghress clan apparently has a history of child abuse. Allegedly, Quain'ana [[spoiler: ordered her soldiers to rape her own daughter Mel'arnach]] when Mel refused to bear an heir for the clan; in turn, according to a non-canon side story, [[spoiler: Mel and Sil'lice raped their adopted sister Syphile]], and Syphile once locked Ariel (who was physically about 5 years old at the time) and Fuzzy (Ariel's cat) in a cell with no bathroom for a week, and then [[spoiler: killed Fuzzy in front of Ariel when Fuzzy bit her]].
** Kharla'ggen, ruler of the Vloz'ress clan, is the page image for LivingDollCollector.
*** It's noteworthy that while Kharla is an adopted member of the clan, the native-born Vloz'ress apparently have a streak of madness a mile wide.
-->'''Kiel'ndia:''' So, what do you think of my home? Sucks, doesn't it? I wonder what was going through their heads when they built this place. "Let us create a monument to immortalize our madness, to be cherished forever by nuts worldwide. All loonies shall live here and despair... MWAHAHAHAHAHA!"
* This problem is endemic in ''Webcomic/GirlGenius''. [[ScienceRelatedMemeticDisorder Sparks]], being creative geniuses with impulse control[=/=]prioritization issues, naturally respond to any intellectual problem or technological innovation with "[[DistractedByTheShiny ooh, shiny]]!" The powerful ones also tend toward considerable charisma and psychological instability. Throw in a lot of "manifest destiny" and "right to rule" noble sentiment, probably lifted from real-world history, and you get feuding warlord dynasties unleashing war machines and fearsome monsters upon one another constantly. AntiVillain Baron Klaus Wulfenbach forged a ''Pax Wulfenbach'' of sorts, but there's still a fair amount of scheming and rebellion against the (perceived) EvilOverlord. Even the heroic Sparks, mainly [[TheChosenOne heir to legendary heroes]] Agatha Heterodyne and her probable love-interest/only viable political rival, Klaus's son Gilgamesh Wulfenbach, are prone to manic episodes of creativity and occasional violence.
** The House of Heterodyne, of which Agatha is the only known living member, deserves special mention. For generations, they were the most insane and dangerous maniacs that the world had ever known, and also some of the strongest Sparks. The previous generation, Agatha's father and uncle, are an exception, having used their brilliant insanity for good; but according to one observer, the [[TheIgor people of her hometown]] would accept a crazy Heterodyne as legitimate:
--->'''Vole:''' De pipple of Mechanicsburg would '''not''' ekcept dot [killing Castle Heterodyne] as proof dot she iz a Heterodyne ... not unless she danced nekked though de ruins vile trying to shoot down de moon -- turned all de tourists into monsters -- and den built a very dangerous fountain out of sausages.
** Add in the fact that the Heterodynes were the ones who created the Jaegers (think UsefulNotes/{{W|orldWarI}}W1 Germans fused with Orkz and muppets) and they were plenty messed up too. Basically, the Heterodynes bred right past crazy and back around to normal.
** Add to this the House Sturmvoraus, apparently affected with an inborn ChronicBackstabbingDisorder, and a Prince in love with [[BigBad The Other]].
* In ''Webcomic/{{Homestuck}}'', the Highbloods [[FantasticCasteSystem (high-ranking members of the troll caste system)]] seem to be innately prone to psychotic behavior. [[CrapsackWorld (Well, more so than the rest of the species.)]] The highest bloodtype; the Imperial, or Tyrian line, boasts [[GodSaveUsFromTheQueen Her Imperious Condescension]], a millennia-old tyrant known for her cruelty and fickleness. (Interestingly, her [[GenerationXerox descendant]] Feferi seems to be much more benevolent, making this part a possible subversion.) Meenah, the Condesce's previous incarnation, says it's a shame she can't be around Feferi because they're both of the highest blood type, she has the irrational urge to murder her descendant to take the throne, no matter how sweet Feferi is. There's also the Grand Highblood, a warlord who often killed and mangled people [[ForTheEvulz for the hell of it]], and [[spoiler: his descendant Gamzee, who eventually snaps and [[AxCrazy brutally murders two of his friends]] over the course of the story.]] Equius, a noble-ranking blueblood, has some [[BerserkButton peculiar anger management issues]] and pretty much states up front that highbloods are just genetically predisposed to violence and psychosis.
* ''Webcomic/TowerOfGod'': Hendo Lok Bloodmadder, head of the noble Hendo family, sacrifices each of his children at the young age of 100 (relatively young for ToG standards) to keep himself immortal. The kids are completely fanatic about daddy.
** Whereas the family of King Zahard seems to be a bunch of quirky young girls with limited amounts of sanity and common sense.
** And, in the [[InJoke Blue Corner]], we have the Koon Family. The Head, Koon Eduan, has many wives and many, many resulting children and grandchildren (and, seeing as this is [[TheAgeless the Tower]]) great-to-the-power-of-who-knows-how-many grandchildren... [[TangledFamilyTree The Family Tree must resemble an overgrown mangrove swamp by now.]] And, they believe in regular attempts at pruning: politics, betrayals, backstabbings and a coming-of-age tradition that's murder on the kids are all parts of their game. This tends to produce [[ManipulativeBastard schemers]] and those with a certain yen towards [[ProperlyParanoid paranoia]] that others in the Tower are wary of.

[[folder:Web Original]]
* [[NotBloodSiblings Zeus and Hera]] and their children in ''Literature/ThaliasMusings'', ranging from good but troubled (Apollo and Artemis) to flat-out crazy (Eris).
* Though not actually royalty, whenever Creator/AchievementHunter does a "King" episode in their ''[[LetsPlay/AchievementHunterMinecraftSeries Let's Play Minecraft]]'' series, if Ryan is king, he will flat-out go nuts. To wit, "King" Michael and "King" Geoff were quite simple in their events; Ryan built a RussianRoulette room and told the other guys to go in and test their luck.

[[folder:Western Animation]]
* Candy Kingdom Law, in ''WesternAnimation/AdventureTime'', is "complicated," according to Princess Bubblegum. In the event that anything should happen to PB, who inherits the throne? Her maladjusted, overly-sensitive, socially awkward, most likely brain-damaged, insensitive, angry, sour-tempered, alienated son/science experiment gone wrong, the Earl of Lemongrab. Arguably, Lemongrab is a pretty sympathetic example of this trope--he obviously has a... [[AmbiguousDisorder delicate condition]], but that doesn't stop everyone from despising his guts for being a JerkAss most of the time and sending everyone to the dungeon for a million years. But why stop there? When the princess realizes her errors, she must create a second heir. This time, she brings her own DNA into the equation in an attempt to stabilize the formula. Enter the giant, pink, infantile being Goliad. Princess Bubblegum wants to educate her in all the ways of royalty and leadership and Finn and Jake are tasked to teach her. However, Goliad's "mondo mama brains" have an extreme imprint. Just seeing Jake yell at a group of preschoolers in order to keep them quiet send her into an authoritarian state in which everyone is forced to follow her rules. Then Goliad pulls out her ThirdEye and begins to control the citizens of the Candy Kingdom with mind control and telekinesis. If not for [[spoiler: Stormo, a being created by Finn's DNA]], the kingdom would have fallen.
** Surely the Candy Kingdom can't have all the fun. There's also the [[{{Hell}} Nightosphere]] and the Vampire Kingdom, controlled by the Abadeers, respectively Hunson and Marceline. Hunson, as the [[ChaoticEvil Lord of Chaos]], controls the strange tortures that flood the Nightosphere. Mutilation, immolation, bananas coming out of orifices; all done in pure glee. His daughter, Marceline the Vampire Queen, is seen less as a ruler and more a fickle [[TheTrickster trickster]]. If she has royal obligations, she completely ignores them.
*** At one point, Marceline was tricked into [[spoiler: becoming the Lord of Chaos by ''her own father''. This made her even more disturbing as she would line up those in the Nightosphere and hand out punishments on whim, giving choices like "pain, pain, or more pain" and asking if someone wanted abs (which she placed on the person's head)]].
** The entire Fire Kingdom court is evil. This includes Finn's new {{Love Interest|s}} Flame Princess, though her father admits that love could turn her chaotic neutral (at the cost of an experience penalty for going against alignment). She's also CuteAndPsycho with a HairTriggerTemper, and if her emotions go out of control [[spoiler:she can ''destroy the world''.]] Her father is also a little too eager to make sure his daughter stays evil.
* The line of the Fire Lords in ''WesternAnimation/AvatarTheLastAirbender'' has... issues. Specifically, a tendency toward being sociopathic and homicidal on both a personal and national level. Again, if there's hope for stopping the ruling lunatics, it seems likely to come from the branches of the tree that didn't get hit with the genocidal batshit crazy stick -- [[DefectorFromDecadence disgraced traitor]] Iroh, or [[TheWoobie screwed-up-but-trying-to-improve]] disgraced traitor Zuko. For the most part the Fire Lords seem to have avoided taking out their issues on their own people, so their own common folks seem to be reasonably pleased with their rulers. It's just everyone else on the planet who's rightfully terrified. The problem isn't likely to go away until the planetary balanced is fixed; it seems to be spiritual in nature. (One ancestor went power-mad three generations back, and his successors have continued his policies. And why not, as they seem to be working fine -- as long as you're Fire Nation, that is.)
* The Heinous family on ''WesternAnimation/JimmyTwoShoes'', which has ruled [[CrapsackWorld Miseryville]] for centeries. You know something's wrong when [[TheCaligula Lucius VII]] is considered the least evil ruler the town's had.

[[folder:Real Life]]
* Henry VI had some kind of mental illness which left him near-catatonic for long periods. It may have been inherited from the French royals; Henry's French grandfather, Charles VI, was also mentally ill, sometimes claiming to be made of glass. Charles's madness led to a civil war, and a English invasion -- Agincourt and UsefulNotes/JoanOfArc; Henry's madness led to the War of the Roses -- two wars, one of which effectively purged the English royal line of madness by almost exterminating it. This shows that occasionally Real Life can be more sensible than fiction: most medieval kings had to be competent, or they got removed.
** Charles VI's madness was triggered by two traumatic events, the first possibly induced by sunstroke, the second by the notorious [[http://en.wikipedia.org/wiki/Bal_des_Ardents "ball of the burning men"]], in which Charles himself came close to being burnt alive. And while Britons like to point the finger at Charles VI as being to blame for Henry VI's madness, it should be noted that his French offspring was not crazy, but actually seemed to have been pretty smart and rational by the standards of their day, in particular his grandson Louis XI, known as [[TheChessmaster the Universal Spider]], and his Louis's daughter Anne de Beaujeu, who very competently ruled France and won another civil war during the minority of her younger brother Charles VIII. Of course to some people the real reason for the troubles of the royal house of France until the 19th century was that Philip the Fair and his successors [[{{Curse}} had been cursed by the]] [[UsefulNotes/TheKnightsTemplar last Grand Master of the Knights Templar when he was burned at the stake]].
** Much later there was UsefulNotes/GeorgeIII, of the "talking-to-a-tree-because-he-thought-it-was-the-king-of-Prussia" style of crazy, but that was an isolated incident and might even have been made up by his son, George IV, who had to rule as regent for years while they waited for him to die. (These are the Georges that turn up in the ''Series/{{Blackadder}} season 3'' finale, incidentally.) The Hanoverian monarchs had an unspoken family tradition of having bad relationships with their oldest sons (from George I and George II to Victoria and Edward VII, not one British monarch had a good relationship with his/her eldest male child) and George IV is known to have cruelly parodied George III's condition in front of his friends in London clubs. IV himself was more a case of 'just about sane enough' than completely well-balanced; fortunately, power was sufficiently shared with Parliament by this time that a sane-ish monarch was good enough, and in any case the only thing George IV ''wanted'' to use power for was to deprive his wife of her privileges as queen.
*** George III only developed madness in later life -- earlier in life he was charming, handsome and reasonably well-adjusted. Recent theories suggest that this may have been due to a genetic condition called porphyria that is hereditary, it just tends to skip several generations without manifesting. May have entered the British Royal Family from the Scottish line James I and VI who may have inherited it from his mother [[UsefulNotes/MaryOfScotland Mary, Queen of Scots]]. Mary, James and George are just the only reigning monarchs to suffer, all the other possible instances just cropped up in branch lines.
*** Skeptics of the theory that George III inherited porphyria from either Mary and James have pointed out that that there is as yet no evidence of porphyria in the intervening generations of Elizabeth, Queen of Bohemia; Sophia, Electress of Hanover; George I; George II; and Frederick, Prince of Wales. Certainly neither Mary nor James displayed any signs of madness. In any case, George III's doctors tried to cure his madness by giving him mercury ("It works on syphilis, maybe it'll cure this too..."), which obviously didn't help.
*** Another doubt is cast on the porphyria idea is that one of its defining features is bluish urine... except George was also being given a herbal sedative which causes blueish urine as one of its known side-effects. There's also the curious fact that he 'got better' for a few years between two attacks of his madness; the descriptions allegedly make the first sound like a long hypermanic episode, and the second (when in his seventies) sound more like dementia than the 'madness' it was described as.
** UsefulNotes/HenryVIII started out as a good king (kind of tough-minded and ambitious, but those were rated as virtues in a renaissance monarch), but became more and more cruel and egotistical as he got older (as many of his wives discovered). Theories differ on why, but illness, a sports-CareerEndingInjury, and [[HeirClubForMen the lack of a backup male heir]] have all been put forward as helping him along the path from arrogant and short-tempered to paranoid megalomaniac.
** The sanity of his daughter Queen Mary I (not only Britain's first undisputed queen regnant (ruling queen)[[note]] Queen Matilda's inheritance sparked a civil war that stopped her from being coronated, and only ended when her rival combatant died after making her son his heir, after which she abdicated.[[/note]] but the original Bloody Mary) is a question historians have never settled. Her campaign to re-establish the Catholic church led to an unusually large number of brutal executions in her six-year reign and brought the country to the point of outright rebellion. Of course, the English Reformation had started as a way for her father to divorce and mistreat her mother, who was then dying of cancer, and witnessing that had a profound effect on Mary. She also may have had a hysterical pregnancy: when she married at 38 she was understandably desperate to produce an heir, as the only other surviving Tudor -- her younger half-sister [[UsefulNotes/ElizabethI Elizabeth]] -- was of questionable legitimacy and very Protestant. Mary was observed by her courtiers to show every sign of pregnancy… but a year went by and no child was born. For centuries it was assumed to be extreme wishful thinking, but the fact that she died soon after suggests it may have been cancer or some other major physical illness.
* The Habsburg dynasty of Austria, the UsefulNotes/HolyRomanEmpire, Spain, and various states in Northern Italy was excessively inbred even by the standards of late medieval European royalty, with a tendency towards mental instability as well as a distinctive underbite known as the "Habsburg lip" that got more disfiguring in later generations. The Habsburgs felt that not marrying "ruling houses" was beneath them and were also devout Catholics, meaning that a large part of German and European families were off limits after the Reformation, unless their partners were ready to convert.[[note]] This for instance was the case with Elisabeth Christine of Brunswick, mother of UsefulNotes/MariaTheresa. [[/note]] To make matters worse, after the Habsburgs split into an Austrian and a Spanish main line after Charles V/Carlos I, the two branches of the family kept trading marriage partners in order to continue to be able to inherit each other's throne should one of them die out. Marrying into the Spanish House of Trastamara in the early 16th century had been a shrewd political move to expand the family's power but a poor choice for genetic health as the pre-Reconquista Spanish houses were already pretty inbred. Even by that low bar, the Trastamaras were noted for their history of oddballs, although the number of truly crazy family members may have been overstated by their enemies.
** [[ComicBook/TheCartoonHistoryOfTheUniverse Larry Gonick's]] take on the Trastamaras was "I'm Pedro El Cruel! What can I do to you?" ...[[TruthInTelevision which was the king in question's real nickname]], [[UnreliableNarrator at least among his enemies]]. His other nickname, "Peter the Just", could be taken to refer to his skill as an administrator... or his penchant for beheadings. (The word in Old Spanish, ''Iusteçero'', roughly translates to "Justiciar" and can mean "enforcer of justice" or "executioner", more or less.) The actual founder of the Trastamara line was Pedro's sane illegitimate half-brother but that didn't keep the unfortunate recessives from popping up in subsequent generations.
** Don Carlos, the rebellious son of Philip II, was insane to the point of being physically dangerous and would take swipes at passing servants with a knife. Philip ended up removing him from the line of succession on the basis that he was unfit for the throne, and he spent the last six months of his life under house arrest.
** Ferdinand I of Austria's favourite occupation was rolling around in the bin.
** The trope's picture is a portrait of Charles II, last Habsburg King of Spain--and portraits included the period equivalent of Photoshopping, so he probably looked even worse in person. He was so severely physically ''and'' mentally disabled (he had the "Habsburg Lip" to such an extent that he could not close his mouth; that's why his tongue is poking out) that his subjects nicknamed him "El Hechizado", "The Bewitched". [[http://en.wikipedia.org/wiki/File:Carlos_segundo80.png His family 'tree' doubles back on itself]]. Taken from [[Wiki/{{Wikipedia}} The Other Wiki]]: According to the medical coroner, Charles' body "[[BodyHorror contained not a single drop of blood, his heart looked like the size of a grain of pepper, his lungs were corroded, his intestines were putrid and gangrenous, he had a single testicle which was as black as carbon and his head was full of water.]]" The only non-Habsburg genes Charles had received in the last ''four'' generations were from his father's '''syphilis''', which was at that point just throwing swamp water up a backed-up sewage line. Unsurprisingly, he closed the Habsburg chapter in Spain by not perpetuating his line ([[{{Squick}} though his advisers tried to get an heir out of him]]). Charles descended from "Juana La Loca" 14 times... twice as a great-great-great grandson, and 12 times further.
** ''All'' Habsburg lines tended to lead back to "Juana la Loca", a.k.a. Queen Joanna the Mad of Aragon and Castille...over and over. It's debatable how mad she actually was and how much of that was genetic versus how much was induced by grief and mistreatment after the death of [[PerfectlyArrangedMarriage her husband]] Philip the Handsome. Witnesses who weren't paid by the rivals to her throne[[note]]Yes, ''her'' throne: technically, she inherited it from her mother, Isabella, and was full queen in her own right, a fact that annoyed her father, husband, and son in turn, as they strove to prevent her from asserting her authority by grabbing it for themselves. Phillip did insert himself as the defacto "coruler" with more clout, but he wasn't a total dick about it, as the major reason was to keep his father-in-law out of his and his wife's business. Which Ferdinand kept trying to meddle in, despite "husband" traditionally trumping "father" in the Control the Damsel game.[[/note]] contested the incidents claimed as the most serious evidence of her insanity, such as repeatedly reopening her dead husband's casket. She probably did have some form of hereditary depression, but her purported "madness" was worst when [[MadwomanInTheAttic she was locked up in a nunnery]] by her own father, Ferdinand, upon her political and military defeats after attempting to pry his claws off her throne after her husband's death -- visitors (particularly outside witnesses) strongly discouraged. Her son, Carlos I/Charles V, later had to be told to treat his poor mother better ''as a condition for election as [[UsefulNotes/HolyRomanEmpire Holy Roman Emperor]]''.[[note]]Yes, this is ''that'' Charles V. The one who might have been ruler of all Europe (save England and France) had it not been for the emergence of Protestantism. That one.[[/note]] Her deplorably neglectful living conditions were quite the open secret and scandal at the time.
*** Joanna was the older sister of Catherine of Aragon, first wife of Henry VIII. Her daughter Mary Tudor wedded her first cousin once removed Philip II, but they never produced a child and Philip eventually remarried with his niece Anne of Austria. Had the English Reformation never happened, the history of the Hapsburgs may have been quite different. On one hand, a Catholic England would have opened up the gene pool a bit for the Habsburgs. On the other hand, England still might not have provided enough genetic diversity if the Habsburgs kept marrying only Habsburgs (it would probably depend on whether the English Habsburgs continued the fine British tradition of having the SpareToTheThrone inherit; the spare could then marry minor Italian and German Catholic nobles), and England might have suffered royal insanity to the same extent as the continent.
** Emperor Ferdinand I of Austria wasn't the head-choppy kind of crazy but he was definitely epileptic and had a hydrocephalus. His (rather euphemistic) honorific was "the Kindly" or "the Benign" (''Ferdinand der Gütige'' in German).[[note]]After his 1848 abdication, jokers sometimes turned this into ''Gütinand der Fertige'': "Goodinand the Finished".[[/note]] He gave exactly one coherent order during his entire reign: upon being told by his cook that he could not have ''[[https://en.wikipedia.org/wiki/Marillenknodel Marillenknödel]]'' (a kind of Austrian sweet dumpling stuffed with whole apricots) for dessert because apricots were out of season, he famously said, "''Ich bin der Kaiser und ich will Knödel!''" ("I am the Emperor, and I want dumplings!").[[note]]He seems to have expressed himself much better in writing; his diary is completely coherent and even witty. Wouldn't be the first time someone with a communication disorder was passed off as dumber than they are to enable a power/money grab.[[/note]] After being told by his chancellor [[MagnificentBastard Metternich]] that the people outside the palace were carrying out a revolution (in 1848), his answer according to urban legend was: "Yes, but are they allowed to do that?"[[note]]Incidentally, he's said to have said it in the [[GermanDialects Viennese dialect of Austrian German]], which (for German-speakers) lends to the air of amiable cluelessness.[[/note]] Since he remained childless, his disabilities did not continue down the line. Not that the line would ever have become Emperors; after the aforementioned revolution, the government convinced him to abdicate in favor of his saner and (it turns out) {{Workaholic}} nephew Franz Joseph (who would reign until 1916).
** The Austrian Habsburgs were restricted to "[[RoyalBlood ruling house]]" of Europe, i.e. of the ruling family of a sovereign European state[[note]](This included families that had ruled states that once were sovereign, such as the family of the Dukes of Modena (who lost their duchy to the the new Kingdom of Italy), from which sprang Zita, consort of Karl I, the last Habsburg emperor)[[/note]] if they wanted their children to inherit the throne(s).[[note]] Most imperial and royal houses followed a rule like this, one notable exception being the United Kingdom, where younger princes were encouraged to marry British noblewomen)[[/note]] This led to a falling-out between Emperor Franz Joseph and his heir-presumptive, Archduke Franz Ferdinand[[note]] Yes, ''that'' Franz Ferdinand. The one who traveled to Sarajevo in June 1914, and whose subsequent assassination precipitated World War I [[/note]]. Franz Ferdinand made the faux pas of morganatically marrying a Czech countess, whose family was not up to imperial and royal snuff, and his children by her were ineligible for the throne.
* Whether or not the Imperial Roman lines count is a matter of much discussion; certainly many of them were raving mad by our standards, particularly, well, [[TheCaligula Caligula]]. For an entertaining view on how insane things got, check out ''Literature/IClaudius''. How much of that was due to the Emperors being corrupted by absolute power, or due to environmental factors such as heavy metal poisoning (a sweeter wine is all well and good, but lead additives aren't going to be a health craze any time soon--and the the Romans were big fans of ''[[http://en.wikipedia.org/wiki/Defrutum defrutum]]'', aka wine that has been boiled down into a thick sauce for use as a condiment, often produced in lead kettles), or how many Emperors just seemed paranoid and vicious because that was the only way to survive as a Roman Emperor (only 29 out of 88 Byzantine Emperors died of natural causes, and at least a dozen were murdered by their own relatives), or how much of the crazy was [[YouFailHistoryForever made up]] by much later historians like Tacitus and Suetonius to serve as [[PoliticallyCorrectHistory parables]], is both debatable and debated. The Empire alternated between periods of military autocracy (where the army essentially chose the leader) and dynasties founded by relatively competent emperors that inevitably descended into murder and madness within a couple generations. A sitting emperor's smartest option was usually to adopt an heir of proven sanity and military aptitude.
* UsefulNotes/QueenVictoria was a hemophilia carrier and passed the gene on to three of her children, from whence it spread to many other European royal houses, royally screwing them over. This included the Romanovs, whose last legitimate heir was doomed to die from this illness before maturity; that's why the faith-healer UsefulNotes/RasputinTheMadMonk gained such sway over the Empress. The hemophilia gene became so prevalent among royals that many commoners thought that hemophilia was ''the'' genetic marker of royalty. Even the 1950s B-movie ''Queen of Blood'' decided that the extraterrestrial featured must be royalty ''solely because she was a hemophiliac''. That is one impressive little allele.
** Not that the Russian royal line needed much help from Queen Vicky. When you've got such kings as [[http://en.wikipedia.org/wiki/Ivan_III_of_Russia Ivan "the Great"]] (yes, he did tonnes; could also start a brutal war over not agreeing with anything any of his brothers liked), [[http://en.wikipedia.org/wiki/Ivan_the_Terrible Ivan "the Terrible"]] (ye gads, the guy knew how to do crazy: and, ran through wives and children at an impressive rate), or even UsefulNotes/PeterTheGreat (who... very much had his moments of darkly-driven, {{Cloudcuckoolander}} bonkers, despite the "Great") indirectly in your genetic back pockets, you've got problems. Even UsefulNotes/CatherineTheGreat's [[http://en.wikipedia.org/wiki/Peter_III_of_Russia husband, Peter III]] was a little unfortunate to have her as a wife (even though they were both far more German than Russian) -- as she probably killed him on the reasonable grounds that Russia having an [[WrittenByTheWinners ardent Russiophobe and Slavic cultural hater and man-child]] on the throne ''wasn't'' exactly working all that well for both domestic and foreign policy (or that was the local perception of what he was maybe trying to do, at least: he was utterly hopeless at explaining himself in a politically acceptable manner, however). And then there's Catherine's son, Paul, who would exile his officers to Siberia for a misplaced coat button and who was assassinated with his eldest son's more or less tacit consent.[[note]] Though he did suffer from horrendous guilt, so it's likely he may have simply intended to lock him up, or just didn't really think over how he would have to deal with his father.[[/note]] No matter what your surname was or who your supposed father was (there are a lot of questions at various points)... the same lesson can be repeatedly found in every Russian linage to hold that throne: don't trust family as they'll probably kill you. Likely on purpose.
* This led to the abolition of the 240-year-old Nepalese monarchy in 2008. In 2001, Crown Prince Dipendra allegedly went AxCrazy and gunned down most of his relatives, including his father the King. By law, Dipendra was crowned Nepal's new king, despite being both accused of multiple murders and comatose from an allegedly self-inflicted gunshot wound. Dipendra quickly succumbed to his injuries and his uncle Gyanedra was crowned king despite being widely suspected of masterminding the royal family massacre. No matter whether Dipendra or Gyanedra had really done it, Nepal had made at least one mass murderer its king. When Gyanedra tried to abolish Parliament, the Nepalese decided they had had enough of this trope and voted to make peace with the [[DirtyCommunists Maoist rebels]] and declare a republic.
* Ancient Egyptian pharaohs made something of a habit of marrying their eldest sisters, to the extent that archaeologists thought for awhile that claim to the throne might have passed through the oldest ''daughter'' of the late king because they couldn't understand why ''else'' so many princesses became their brothers' Great Royal Wives. Current theory says that it was in fact male-line inheritance and that many of the marriages were symbolic, meant to prevent princesses from marrying other men and establishing cadet branches of the royal family. HOWEVER the imperative to secure the bloodline (and a general Egyptian distaste for marrying non-Egyptians) meant that some of those sibling marriages were also ''not'' purely symbolic. The Ptolemaic dynasty (which was ethnically Greek but very quickly assimilated to pharonic tradition) in particular had a Moebius family tree and it kind of showed in some of the later Ptolemies, Berenices, and Cleopatras (historical accounts indicate that UsefulNotes/CleopatraVII, the one everyone remembers, was unusually charming and savvy by her family's standards).
* They're not officially royalty, but for all intents and purposes the severely messed up Kim family are the hereditary rulers of UsefulNotes/NorthKorea. Their antics include releasing truly insane propaganda to the world which depicts their country as a wealthy and powerful developed nation (in fact their level of development ranges from UsefulNotes/ColdWar era to downright medieval), claiming magical powers and impossible achievements (inventing the hamburger and communicating winning strategies to Olympic coaches through invisible phones are among the tamer ones), all but [[GodEmperor deifying themselves]], [[https://en.wikipedia.org/wiki/Let%27s_trim_our_hair_in_accordance_with_the_socialist_lifestyle releasing a list of approved hairstyles for their subjects]], threatening the use of nuclear weapons at the slightest provocation, abducting people worldwide for purposes ranging from creating a {{Kaiju}} film to [[SexSlave sexual slavery]] to teaching English to spies, running a frightening amount of concentration camps which imprison whole families down to the third generation and generally treating their people like disposable chattel.
* The House of Saud, the rulers of Saudi Arabia. Leaving aside how they treat their own people, subjecting them to one of the harshest forms of Sharia law on Earth, with beheadings and crucifixions as common punishment, their personal behaviour often beggars belief, with accusations ranging from murder, rape, drug smuggling and mutilating a maid. As well as this, branches of the family are allegedly linked to terrorist groups such as Al Qaeda and ISIL, and most recently they've been accused of war crimes and attempted ethnic cleansing in Yemen. The somewhat peculiar line of succession that the house practiced for decades (with [[UsefulNotes/AbdulAzizIbnSaud Ibn Saud]]'s ''many'' sons ''all'' being placed before his grandsons) that all but guaranteed repeated brief reigns by elderly kings hasn't particularly lent itself to stability either. This last point seems to be changing, however. In 2015, the current king removed his younger half-brother (these two are the last of Ibn Saud's surviving sons) from the succession and replaced him with one of the grandsons—and he isn't anywhere close to being the oldest living male in that generation.
* Ibn Khaldun's surviving work deals specifically with North African bedouins, but he established a more generally applicable generational succession for nomads and the civilizations they conquer: the first generation is rough and tribal and not quite civilized, the second (with luck) still understands what made his father strong but also has been brought up in the arms of city culture, the third begins to lose touch and grow soft, and after that discipline just fall apart until the next new dynasty rides in and replaces them. Rinse, repeat. Ibn Khaldun was one of the first historians to have a theory of history instead of just a straightforward record of what happened. The Islamic dynasties of Spain are an excellent example of this paradigm and WeHaveBecomeComplacent on this very wiki is a relative of his theories. While he mostly gave North African examples, you have to bear in mind that the ''Muqaddimah'' (which is where these theories come from) was actually the ''introduction'' to a much larger history of North Africa and the Mediterranean (''muqaddimah'' just means "introduction" in Arabic). With the possible exception of the Roman and Egyptian empires, pretty much every great empire of the Mediterranean region in the pre-modern era was founded by at best half-civilized conquerors who took over the established civilizations: the Akkadians, Assyrians, Hittites, Persians, Macedonians, Germans, Arabs, and Turks (to name only the most obvious examples) all did this. Even the Romans were pretty uncouth when they started taking over Italy; between their militarism, agrarianism, lack of high culture, and piety,[[note]]Rome was noted as the most pious city in Italy in that era[[/note]] the perception the Etruscans and peninsular Greeks had of the Romans was the Classical Antiquity version of FlyoverCountry. And as for the Egyptians, they only expanded to become a true empire after their country was conquered by foreign barbarians (the "Hyksos", who were probably Canaanite shepherds), and they won that empire by adopting the barbarians' technology and tactics.
* UsefulNotes/LudwigIIOfBavaria was considered by many to be mad, and deposed because of it (based on the "diagnosis" of Dr. Gudden, who wrote it without ever having met Ludwig in person), followed by his death the next day of either murder or suicide. For the most part his 'insanity' consisted of an obsession with building [[Film/ChittyChittyBangBang elaborate castles]], swans, opera music, and beautiful men, and he's more fondly remembered now -- he's known as the ''Fairytale King'' or the ''Swan King''. Aw.
** After that, his brother and successor, King Otto, spent his entire "reign" institutionalised. (He'd already been declared mad and consigned to an asylum during Ludwig's reign.)
** Some Bavarians like to blame the madness of (possibly) Ludwig and (definitely) Otto on their Prussian mother Marie, pointing at the case of Frederick William IV (uncle of Marie of Bavaria), however new evidence suggests that the Frederick William did not actually go mad but suffered from the effects of a stroke in his later years, which his Bavarian consort Queen Elisabeth tried to hide from the public.
* Like Roman elites poisoned by their lead plumbing, [[http://blogs.plos.org/speakeasyscience/2012/04/20/the-eternal-hour-of-lead/ research]] on remains of samurai children buried at a Japanese Buddhist temple showed sky-high lead levels believed to be from the lead-based white face powder used by upper-class women. Chronic heavy metal poisoning may have contributed to political instability and the decline of centuries-old shogun system in the latter half of the 19th century.
* Some Biblical scholars believe [[http://en.wikipedia.org/wiki/Saul King Saul]] may have been schizophrenic. Not only because of his jealous obsession with and multiple murder attempts against his eventual successor UsefulNotes/KingDavid, but also because he threw a spear at his own son [[http://en.wikipedia.org/wiki/Jonathan_(1_Samuel) Jonathan]] for merely asking why his best friend David had to die (1 Samuel 20:30).
** The text suggests he had severe migraine headaches, which can also make a person behave very irrationally and cause memory loss. He initially brought David to the palace because his doctors prescribed music to help him relax (1 Samuel 16:23) -- this is when the spear-throwing started, as he came to realize that while David wasn't after the throne, he was destined to succeed him. His actions were savage, perhaps irrational, but not schizophrenic.
* [[https://en.wikipedia.org/wiki/Emperor_Taisho Emperor Yoshihito/Taisho]] of Japan, due to a combination of inbreeding and a bout of meningitis that he suffered when he was weeks old and probably left him brain-damaged, was known for bizarre behavior in his later years. During a parade, he reportedly hopped off the royal float and hugged a random trumpet player in the accompanying band, and also behaved rather weirdly during the inaguration of the Japanese Parliament in 1913. As a result, he was kept out of view of the public as much as possible.
* Frederick William I of Prussia had porphyria, and also liked to carry a wooden cane, much to the regret of everyone around him -- he chased his children around the palace with it and was known for randomly attacking commoners[[note]]Who naturally couldn't defend themselves, as attacking the king was treason, a crime worthy of execution.[[/note]] in the streets of Berlin, hollering at them: "You're supposed to love me, not fear me!" This seems to have had a negative effect in his relationship with his son, UsefulNotes/FrederickTheGreat, although the mutual intense antipathy between the two surely didn't help.
* Countess Anna de Coligny (1624-80) was distantly related to the Kings of England and Prussia. She suffered from an illness. Her problems started young. She, while young, was reported to have tried to climb up the tapestries hanging from a wall after a seizure, and she did not get better. Four of her five daughters also went crazy (one had to be locked up in an apartment with ''padded walls''). Her surviving son, while not insane, was very promiscuous and thought it would be a good idea for some of his illegitimate children to marry their half-siblings.
* Many Ottoman emperors have been known to fall into this, but not because of their genetics, but rather because of their upbringing. Whereas the traditional inheritance rule among them dictated that the most skilled son of the predecessor would inherit (read: the most ruthless one who was cool enough with [[CainAndAbel simply murdering his (half-)brothers]]), Sultan Ahmed I. decided instead to spare his younger brother Mustafa upon his ascension, and, in order to still isolate him from politics and potential rebels who might have wanted to use him in plots to overthrow the ruler, he simply locked the latter into the palace (and often only a small number of rooms, at that) in a sort of GildedCage way for his entire life. This took an enormous emotional toll on the young prince, who upon Ahmed's death several years later, was rendered a psychological wreck, with severe neurosis and hallucinations. Although he followed his brother on the throne, he reigned for barely a year before the courtiers locked him up again (He later reigned a second time, again for barely a year). Ahmed's own sons who succeeded Mustafa, were also barely saner, with most of them proving to be {{Mood Swinger}}s with heavy paranoia: His first son Osman was a RoyalBrat who used courtiers for target practice with his Longbow, his second son Murad a choleric KnightTemplar who had almost all of his Viziers executed during his reign and a lot of Istanbul's population sent to the henchman for crimes like drinking coffee, and his last son Ibrahim was literally nicknamed "the mad" (but not for being AxCrazy, but rather because of [[AnythingThatMoves how many women he knocked up]] (which was not all that bad a thing, too, because Murad had no children and slaughtered almost all of his (half-)brothers during his reign)). Most historicians today consider this one of the main reasons why the Ottoman Empire gradually collapsed.
* On the pathetic side, there is the Duke of Angoulême, son of Charles X of France. Unlike his father and his more charismatic brother, the Duke of Berry, he was frail, suffering from many nervous tics and probably impotent, which at least prevented him from having even more screwed-up offspring with his wife and first cousin, Marie-Thérèse, daughter of Louis XVI and Marie-Antoinette. He did ascend the French throne during the July Revolution... for all of 20 minutes, and even then most Legitimist partisans refused to acknowledge his claim to the throne.
* Chinese emperor Shi Huang Di became ''extremely'' paranoid towards the end of his life. This is because he drank ''mercury'' every day, believing that it would make him immortal.
* The Oldenburg dynasty in Denmark, beginning with Christian I, deserves some notes here. Most of the kings were fairly sensible at best, and dimwitted at worst, known to screw up badly in foreign affairs. Then [[https://en.wikipedia.org/wiki/Christian_VII_of_Denmark Christian VII]] came along. He suffered from mental illness, and had to rule by proxy for long periods of time. Christian suffered from hallucinations and paranoia, and his reign coincided with that of English George III (mentally ill kings were somewhat fashionable at this time). His illness led to the infamous ''Struensee affair'', when the King´s physician took the helm in his name and turned out to be the most sensible ruler Denmark had had for decades, until he was toppled in a coup and executed. His son, Frederick VI, had to rule in his name from that point and onwards, and is known for having messed up big time when he eventually became king. This because he was the unlucky bastard who had to steer Denmark through the NapoleonicWars, and screwed up enough to be partly responsible for the UsefulNotes/NorwegianConstituentAssembly. The dynasty died out with Frederick VII, and the Glüksborg branch turned out to be a ''lot'' more sensible, but then they were ''constitutional'' monarchs.