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When there is no male heir, a Succession Crisis results, which is reason enough for kings to go to great lengths to ensure that he has at least one son on the ground who is his clear and legitimate offspring and the authorized heir to the throne.
If the King has no son, or circumstances seem to be making that problematic, the courtiers may get into the act. A Succession Crisis can be unpleasant all around. This is done commonly with a grieving widow Queen or widower King, who is likely to be told You Have Waited Long Enough with great promptness.
Even in the fortunate case where the King has a healthy male heir, this only secures the monarchy for one generation. As soon as that son comes of age, he will start feeling pressure to marry and produce an heir of his own. And only one child is dangerous; surely you need at least two. This is one of the few situations where either My Biological Clock Is Ticking or I Want Grandkids is likely to apply to a male character.
Then again, any old child will not do; for men at least, Mama's Baby, Papa's Maybe may raise doubts about whether the baby actually is suitable. Still, some monarchs will avoid putting all their eggs in one basket and make the spare a Hidden Backup Prince (bastards of the king are popular for fulfilling both these tropes).
Although most common in stories about royalty, this trope also includes the common people. This trope is about heirs, and it is not intended to cover cases where the parent(s) merely wish for a boy (or girl) because they would like one, but is only when they wish for one to continue the family name—when tradition demands it.
Also: The blurb is a reference to the Hair Club for Men, a company that specializes in hair restoration and hair replacement. The blurb is their actual sales pitch from their web site... with a few words changed to fit this trope.
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The plot driver of Ribon No Kishi, aka Princess Knight, which provided direct inspiration for other mangas like Rose of Versailles. A male heir must inherit the throne, Sapphire is born with a conspicuous lack of penis, her father the king decides to bluff the public and Sapphire becomes a Wholesome Crossdresser.
Rishid in the original was adopted by the Ishtars to provide a male heir. Then Ishizu and Marik were born in turn. A particularly potent example: Rishid/Odion desires the position of Tombkeeper more than anything, whilst Marik wants nothing more than to be rid of it.
Needing a male heir, in particular a biological one, is the source of much of the trouble related to adopted child Amon in Yu-Gi-Oh! GX.
Miroku of InuYasha needs to perpetuate his line (with a son) before the affliction that plagues all men in his family kills him. He attempts to do so by propositioning every girl he meets. He loses the affliction before the end of the story, but has at least three kids anyway with Sango, and one's a boy.
In the fictional Kingdom of Sauville in Gosick, the Queen Coco Rose was deposed of by King Rupert because of her inability to bear a child. Which later turns out to be a ruse: It was King Rupert who was sterile. To add insult to injury, Coco Rose became pregnant... with Leviathan the Alchemist's child.
Thought to happen in Syaoran's family in Cardcaptor Sakura, as he is considered the head of his family (despite having four older sisters) since his father passed away. This status is limited in Syaoran's case, however, given his young age. It puts a lot of pressure on him.
This is why Ryuunosuke Fujinami was Raised as the Opposite Gender in Urusei Yatsura; her father was obsessed with the idea that only a boy could be a worthy heir to his family legacy of... running a ratty little beachside store. This is used for roughly equal parts comedy and to paint Mr. Fujinami as creepy and insane.
Twisted in the Child BalladFause Foodrage. Aware that only a son would be a serious danger to him, the king's killer tells the queen that he will spare a daughter but kill a son. The queen escapes and persuades a noble to take her son and give her his daughter. In due course, the son returns to kill the king's killer and take the throne.
In Amethyst Princess of Gemworld Dark Opal's repeatedly attempted to get himself an heir, but his own children are all misshapen and he locks them away in another dimension, except Granch, who understandably rebels against him. Then he "adopts" Carnelian, an earthling and that ends up much the same way.
The Invisibles: Transvestite shaman Lord Fanny was born a boy in a family with a long line of brujas. After his mother's second attempt to have a child ended in a miscarriage, his grandmother ordered him to be raised as a girl. Fortunately, Fanny took quickly to crossdressing, and ably took up the family tradition.
Ra's al Ghul needs an heir to take over his criminal empire, who must marry his daughter to inherit. Batman from the animated series once referred to him as "the world's oldest chauvinist" (especially since Talia has proven at least as capable as Pops). Ghulie's somewhat successful when Talia conceived Damian.
A modern, political example happens in Sin City. The Roarke family is the most powerful family in the country and corrupt to the core. They have been running the city for over a century but during the events of the series, there was only one heir to the "royal family": Junior Roarke, a Serial Killer and child molester. Junior is castrated and later killed by Detective John Hartigan, resulting in the Roarke legacy being cut off for good.
What about The Phantom, Lee Falk's masked hero? The current Phantom is number 21. Both the suit and the title always go from father to son. The chances of 21 generations conceiving only male heirs (and only one male heir, because there's never any mention about secondary sons) aren't exactly very high. One historical Phantom did a have a daughter though - she worked a while as a female Phantom until her brother took the mask. There's never any mention about any other close relatives as well. Of course, every Phantom needs not just to conceive a male heir, he also has to survive just long enough for his son to grow up. Once his son is old enough (16-20), the old Phantom conveniently kicks the bucket so his son can swear revenge and become the next Phantom. There's no retirement house in Florida for Phantom senior, because every Phantom beyond 40-50 years is most likely dead.
The king and queen in "Donkeyskin" only had a daughter, and were content with this. But the queen fell ill and died without leaving a male heir, but not before saddling him with the additional restriction that his new wife equal her in beauty and other attributes. Which, after many failed considerations, leads him to the conclusion that his new wife should be his own daughter. Because that would be more acceptable than simply letting her inherit the throne. She manages to escape that situation, and marry a prince, to boot. Thankfully, the prince is not her brother.
In "Catskin", the nobleman doesn't care about his daughter because he wants a son. When she grows up, he orders her married off to the first man who will have her and she has to run away.
A commonfan theory for why Scar chose Kovu as his heir is that Nuka was too weak and idiotic and Vitani was female. It's actually a major plot point in the third part of the fan webcomic, The Relatives of the King, where Zira and Scar keep having cubs in an effort to produce a strong, male heir. In the end, they just end up adopting (or more accuratly stealing) Kovu and proclaiming him next in line.
In Pan's Labyrinth, Captain Vidal is determined to have a male heir no matter the cost to his wife or his stepdaughter.
The fact that only males can inherit the throne in Stardust means that Princess Una isn't a target of her other brothers, who are busy killing each other off because the law also demands that there be only one male contender. It helps they have no idea where she is.
The emperor from Caligula refused to marry Caesonia until she bore him a son. When his sister Drusilla pointed out that it would be impossible to tell if the child was actually his, he replied that he would simply keep her under constant guard. The guards would be homosexuals. Who'd been castrated.
The king in Fantaghiro really insists on having a male heir, as (paraphrased) when his third child was born:
King:(as servant brings the baby) I have no doubt it's a prince this time! You will bow to him, daughters, for he is SUPERIOR!
(unwraps the baby on-screen, vagina ensues)
King: A GIRL? What SORCERY is this? That white which must have CURSED me!
Possible examples in The Thief Of Bagdad; Jaffar's stated reason for asking for the hand of the princess of Basra is that he wants to start a dynasty. The sultan of Basra then says, "I tried that once, and what have I got? A daughter!" (Of course, Jaffar is a usurper, for whom having a marriage and heir with royal blood would probably be a bit more important.)
Frederich is shown praying desperately for a son in Snow White A Taleof Terror. It seems to be the only reason he married Claudia as he is still in love with his dead wife. Claudia, who admitted to her mirror that she really loved him, is not happy when she realizes this.
Played with in Gladiator, as Marcus Aurelius laments that Lucilla was not born a man, noting "What a Caesar you would have been," to her. Only to deny her brother and expected blood heir the throne and promise it to Maximus instead, setting off the events of the movie.
Young Frankenstein: The deleted scene where the contents of Baron Frankenstein's will were revealed: On his will, Baron Frankenstein described Frederick as his only male heir and never considered leaving anything to his granddaughter.
One of the major plot motivators in Jane Austen's Pride and Prejudice is the Bennetts' lack of a male heir. Their family estate is entailed, which means that it is bound legally to be inherited by the next male relative in the family line. It's their distant cousin, Mr Collins. He kind of felt for the Bennet sisters and proposed to one of them; however, she didn't want to marry a stupid and obnoxious person because of property.
Persuasion by Jane Austen: Sir Walter's estate Kellynch Hall is entailed and he has no son. His heir presumptive is Mr Elliot, a distant cousin to his daughters. The family wished he would marry the eldest daughter Elizabeth, but he married a low-born woman for money. When he became a widower, he set his eyes on the younger Elliot daughter Anne, who though not as handsome as her sister is very intelligent, gentle and nearly an angel. He appreciates her character, however, his strongest motive to remarry is to be closer to the family so that he can keep an eye on Sir Walter (also widowed) who might get married again soon and produce a son of his own after all, which would cut his inheritance of the baronetcy and the estate.
In C. S. Lewis' Till We Have Faces, the king of Glome wants a male heir and gets three daughters. His anger about this is the source of much tension in his family and the court. In the end, his oldest daughter seizes, and holds, the throne after his death.
The Silmarillion: The kingdom of Númenor had a Agnatic Primogeniture law applied to its line of Kings. Tar-Aldarion, having no male heirs and having only a daughter, changed the Law of Succession, replacing the principle of agnatic primogeniture with that of fully equal primogeniture and she (as Tar-Ancalimë) became the first Ruling Queen of Númenor. Afterwards, the oldest child inherited the throne whether they were male or female.
His legal changes were largely undone in practise, however, as only two other queens claimed the throne in the next 16 generations. The odds of this happening by pure chance are extremely low, assuming male and female royal offspring were equally likely to be born and survive to inherit.
In the original novel, Duke Leto's concubine Lady Jessica was supposed to have a daughter for the Bene Gesserit, but Leto wanted a son, and she went along with him, although it is not made clear if he wanted a son for reasons of getting an heir or just wanted a son because he wanted a male child.
This is added to by the fact that the Bene Gesserit's Xanatos Roulette was aiming for a daughter so that they could produce a male heir with a Harkonnen. Making the Bene Gesserit a Heir Club for Witches?
In the Dune prequels, the Emperor's wife deliberately prevented this, probably under orders from the Reverend Mothers, who planned to bring the Kwisatz Haderach into existence within a few generations, and needed the throne empty for him to assume.
In Robert Jordan's The Wheel of Time, Andor is always ruled by a queen, and it's said that no man has ever survived sitting on the Lion Throne. Every so often there are minor "wars of succession" because it's unclear which woman is next in line.
The Assassins Of Tamurin: The success of Makina Seval's plot hinges on her adopted daughter Ashken having a male heir with Ardavan. Nilang assures Lale she has a contingency plan — if Ashken's first child should happen to be female, she will quickly be Switched at Birth with a male child before anyone is the wiser.
In Lois McMaster Bujold's The Curse of Chalion, Roya Orico grasped that the titular curse lay with him and convinced his Royina to secretly lie with his (evil) Chancellor (who was at least polite about it) and said Chancellor's even more evil brother (who was not). When that plan proved unsuccessful (and Royina Sara threatened to kill herself), he summoned his much younger half brother Tediz to court along with his sister Iselle. Bujold eventually subverts it when Iselle (the bright one to begin with) is left the last of Fonsa's line alive when the titular curse is finally broken.
In the first book of Melanie Rawn's Sunrunner series, Dragon Prince, the realm is in an incredibly fragile political situation due solely to the fact High Prince Roelstra has seventeen daughters, yet no male heir; like Henry VIII in real life, Roelstra has put aside wife after wife, and his daughters (legitimate and illegitimate) are both opportunists and opportunities, politically. One of the book's key intrigues rests on ensuring (via an elaborate deception) that Roelstra's fourth and current wife bears — or appears to bear — a son.
The Jargoon Pard: Lady Heroise is determined to bear a son she can mold into her puppet and so rule Car do Prawn. Unfortunately her child is a daughter. Luckily the expectant couple in the next room has just delivered a son. But unbeknownst to Heroise the father just happens to be her own long lost half-brother....!
The Crystal Gryphon and the prequel short story "Of the Shaping of Ulm's Heir" are begun by this trope. Lord Ulric of Ulmsdale had been unable to father any living children, so he divorced his second wife and married the widowed Lady Tephana because she was of proven fertility, having a son from a previous marriage. This led to a great deal of trouble starting at the end of the short story and picking up at the beginning of the novel, when Lady Tephana utterly rejected her son by Ulric - Kerovan - and settled down to scheming on behalf of her first-marriage son and later her daughter by Ulric. (The latter could inherit if Kerovan died or was publicly rejected as being unqualified to rule, e.g. because of mental or physical infirmity).
Joisan, the female lead of The Crystal Gryphon is involved in another potential Succession Crisis. Her paternal uncle, the lord of Ithdale, has no children but two potential heirs: Joisan (his half-brother's only child) and his younger sister's son, Toross. Although Joisan has been in an Arranged Marriage since early childhood, Toross's mother keeps trying to throw her together with Toross in the hopes of securing the succession for him. And Toross goes along with it because he's genuinely in love with Joisan.
In Piers Anthony's A Spell For Chameleon, the Magician Trent must marry the Sorceress Iris in order to remain in Xanth; this condition is set because only Magicians can rule in Xanth, and in hopes that their powers will ensure that they have a Magician son. In The Source of Magic, the widowed Trent has difficulty ensuring an heir because he's still in love with his first wife; they do succeed, in time, in having a child, but a daughter. Finally, in Night Mare, when Magicians are being removed as soon as they are King, during an invasion, Loophole Abuse is invoked: the laws of Xanth forbid a ruling queen, but do not explicitly require that kings be male. Sorceresses, both Iris and her daughter, ascend the throne as Kings.
The entire plot of the Merry Gentry series is The Fair Folk being mostly infertile, and whether Prince Cel or Merry can deliver an heir first.
The House of Rahl takes it a step further: Not only must they have a male heir, but the heir must have the magical gift. More recent generations (particularly Darken Rahl) took to killing any female and/or non-gifted children.
Inverted in the case of the Confessors. Any male child of a Confessor had to be killed because they invariably ended up abusing their power.
The cause of more than a few problems in Robin Hobb's The Farseer. Chivalry, the crown prince, caused a scandal when he married who he wanted instead of for politics, and then she turned out to be too infirm to carry a child to term. When word came that Chivalry had a bastard son, Fitz, he stepped down in favor of his brother, Verity. Verity eventually marries but wrecks his health so much with using the magical Skill that he can't father children, so Verity takes over Fitz's body to have sex with his wife in hopes of continuing the royal line, even if through a bastard, since the Skill is strongest in the royal bloodline and if lost there may die out altogether.
A side plot in the Last Herald-Mage trilogy by Mercedes Lackey is that King Randale of Valdemar is sterile. To hide this fact, Vanyel sires a child on Randale's lifebonded mate (at her request).
Barrayar has Emperor Gregor, last of a Royally Screwed Up line of emperors, who seemed quite averse to marriage and heir-production. Which caused no end of trouble for his Prime Minister, Aral Vorkosigan, who was arguably the most legitimate claimant to the throne but adamantly did not want the job. Naturally, Aral's son Miles spent a lot of time fretting too.
Honor Harrington example: The Star Kingdom of Manticore has allowed primary succession by women ever since their second monarch, Elizabeth the First. The current queen is Elizabeth the Third. Grayson has recently tweaked the law to allow women to inherit (with a grandfather clause for current heirs), especially making sense due to the population being 75% female. The Andermani had a better solution: their first female Emperor, Gustav VII, dealt with rules forbidding female inheritance by declaring herself to be a man. It helped she took control of the Imperial Fleet before hand. "He" is considered one of the best rulers of an empire whose rulers are well known for their eccentricities.
Darkover is obsessed with this trope and wanting sons, though with several exceptions. The Aillard line is matriarchal and matrilineal, and Renunciates are forbidden from playing the game; they must vow to never make a traditional royal marriage or become a concubine, and "to bear children only in [their] own time and season," not for their family's ambitions. This is justified because laran is determined genetically.
This trope is played with by Sheri S. Tepper in three novels. In Six Moon Dance the founding mothers of the planet Newholme create an artificial scarcity of female babies, and a dominant ideology that females are the stronger sex and males are the weaker, leading to the population desiring female heirs. In Raising the Stones the power derived by males from their heirs is eradicated by legally denying the father-child relationship. Heirs are are only accepted through the maternal line, and any male claiming fathership is frowned upon. And in The Gate To Women's Country the women and men of the story live in different quarters, and when a male comes of age they must choose which quarter they permanently wish to live in. If they, for example, choose the men?s quarter, then their mother can no longer claim them as an heir; if they choose the women?s quarter, then the father no longer has fathership.
A particularly ironic lampshade is placed on Rhys in Katharine Kerr's Deverry Cycle, when he puts aside his wife for being infertile...and she remarries and is immediately knocked up by her new husband, much to the amusement of everyone involved, except Rhys.
In The Castle of Otranto, a nobleman's sole male heir is mysteriously killed, and he immediately begins making plans to marry his late son's fiancee, annulling his current marriage and consigning his wife and daughter to ruin. Played with, in that he acts this way because he fears that failure to produce another son will bring an ancestral curse down on him, not because he actually cares about his bloodline's future.
In Coin of the Realm, Princess Rosalind's father had six daughters before finally getting the son he wanted to succeed him. He regards his daughters as nothing more than "coin to be traded", with no more value than whatever he can get for marrying them off. This, naturally, doesn't sit well with Rosalind at all.
In Lynda Robinson's Lord Meren mysteries, in which Meren is perfectly happy having his adopted son Kysen as his legal heir. His relatives, on the other hand, loathe the idea of a common-born adoptee carrying on the family name, and keep badgering the widowed Meren to remarry and produce a "proper" son.
An inverted non-royal example in Anne Rice's Queen of the Damned. Maharet, one of the first vampires, had a daughter before being turned. Since then, she has tracked all of her matrilineal descendants without regard for any descendants of males. While this made more sense in ancient times without reliable (or any kind) paternity testing (although she did assume that all women cheat), this is more of a tradition than anything in modern times.
In Robert E. Howard's stories of Conan the Barbarian after he became king, several times it is a plot point that Conan's death creates a problem, as he has no son. Oddly enough, we never see any pressure on him to marry and have one, though in other stories he does eventually get married and have a son.
In Cornelia Funke's Inkheart series, the Adderhead is terrified of death; and somehow this makes him think he needs a male heir.
The Star Wars Expanded Universe gives us the misandrist Hapans. But Ta'a Chume never had a daughter, so her daughter-in-law, from the primitive and even more misandrist Dathomiri, becomes the new queen. But mostly she doesn't want Jedi to rule her kingdom. Three guesses what religion her granddaughter joins.
Male heirs are the norm in Safehold, with the Princedom of Corisande being of particular note, as Prince Hektor regards his heir as an Inadequate Inheritor, and would gladly make his daughter Irys the heir of Corisandian law allowed it. There are exceptions though, primarily with Sharleyan of Chisholm, who inherited, and kept, the Crown despite the shadow of a less competent queen hanging over her. She later became the co-ruler and The Lancer to Cayleb of Charis, and nobody has any doubt that Cayelb and Sharleyan's daughter Alahnah will be their heir in the fullness of time.
Septimus Heap has only female Queens. Men can't become rulers, and there never were any Kings; even the idea is deemed ludicrous.
The nobility of Westeros practice a form of male-preference cognatic primogeniture, meaning that lordly titles are passed down from father to eldest son. A younger son could inherit if his elder brother dies without any male issue, and a female heir could only inherit if she has no surviving brothers and none of her brothers had any male issue. Even then, families often cast a wide net to find a male heir among the cadet branches and other distant relations rather than allow a female to hold power in her own right. This is because should a female heir marry, her husband would take power of her inheritance through her, more or less starting a new house traced through his own line and cutting out the existing family entirely. This has implications when daughters of defeated noble houses are forced into marriage with the victors, that the victor's family might lay claim to the defeated family's holdings.
This is certainly the case later on in the books. After Robb Stark's death at the Red Wedding and the presumed death of his two younger brothers, Sansa is the presumptive heir of the Stark family. Accordingly, as the spoils of war, Lord Tywin marries his son Tyrion to her; as the husband to the Stark's rightful heir, Tyrion could then rule the North in the name of House Lannister. But Robb throws a wrench in the works when he disinherits Sansa in his will and names another heir, thought by most fans to be Jon Snow.
Unlike the rest of Westeros, Dorne exercises absolute cognatic primogeniture, wherein the eldest child of the ruler inherits, period. Like most legal snafus, this causes trouble when the Prince of Dorne's daughter schemes to make Myrcella Baratheon/Lannister the queen of the Seven Kingdoms, as by Dorne's laws she would be the rightful heir. Part of her scheming comes from a plot by Prince Doran that (mistakenly) makes her believe that he means to scam her out of her rights in favor of her younger brother.
Subverted in the case of the Dothraki. Daenerys expects her unborn son to become the heir to Khal Drogo's khalasar simply by being his child after Drogo dies, but Jorah Mormont tells her that the Dothraki do not honor blood and will only follow the strongest. The khalasar is then splintered by new khals who take the remnants, while Daenerys is left with around 100, consisting of her bloodriders, handmaidens, old men, women, and children. And even then, it takes the birth of her dragons until they accept her as leader. Drogo himself is the son of a great khal, Bharbo, but did not inherit his father's armies. It is also noted that Drogo is a very young khal, leading an immense khalasar of his own before the age of 30.
In The Forgotten Beasts of Eld, the baby Tamlorn's mother is Sybel's aunt, who married King Drede. His father is either the king, in which case he's the heir, or another man, who the king killed in a fit of jealousy, which is why Tam's life is in danger, especially since in the latter case, he could be a pretender for the king's rivals to gather around.
In the Tales Of The Branion Realm, equal primogeniture is used, possibly because the sovereign doubles as a religious avatar and the God in question neither recognizes nor cares about gender. It doesn't care about bastardy either, which drives the plot of the third book when the royal family has converted to a different faith and a woman seduces the monarch to bear his firstborn. A civil war ensues.
Live Action TV
An episode of The West Wing features a muck-raking and inaccurate 'expose' memoir from a former staffer fired for incompetence which, amongst other things, alleges that the President wore special undergarments in order to produce a male heir when conceiving the child that ended up being his youngest daughter. The President is bemused, to say the least.
The episode "Heart of Gold" of Firefly has Burgess, a man who accidentally knocked up a whore and wants the child, as it is male, for an heir. It's heavily implied that he didn't do it accidentally; rather, Burgess' wife is implied to be infertile. When he receives the news that it's a boy, his wife is present and appears to be as relieved as Burgess is.
The Tudors has this in spades, not surprisingly considering that it's a show about Henry VIII.
In Robin Hood, Guy of Gisborne makes it very clear on a couple of occasions that he expects Marian to provide him with an heir as soon as possible. He even uses it as a pick up line after the death of her father.
What better way to grieve than to create new life?
Downton Abbey has a plot related to the entail of the estate, which is a similar issue to the situation in Pride and Prejudice whereby the daughters cannot inherit and the male heir is somewhat distant to the family (he's the Earl's fifth cousin). Fortunately, the heir-presumptive is a young bachelor of an age where he could marry one of the current Earl's daughters — particularly the eldest, Lady Mary — and keep the property and title in the family. He does — marrying Mary (who, as it turns out, is perfect for him) and producing an heir — but there's a lot of drama before they get there.
The Palace featured a haughty princess scheming to dethrone her younger brother by destroying his reputation. (There was also another brother in line before her, but getting rid of him would be a piece of cake — assuming the public even let him become king in the first place.)
Merlin When Uther couldn't get an heir, he turned to magic, and it gave him one, but cost him the life of his queen, Ygraine.
The NCIS episode "Newborn King" features a Marine who was sent home after she got pregnant from a fling with a soldier from Afghanistan. The father turned out to be the only heir to a tribe that owned a valuable piece of land, and when he died, his family became very interested in getting their hands on that baby, sending a trio of Russian mercenaries after the Marine. It all ends up for naught, as not only does Team Gibbs subdue the mercenaries, but the Marine gives birth to a girl, who is ineligible to inherit.
A version that pops up in Smallville has to count. Lionel Luthor might not have been all that concerned with his son, but when his Alternate Universe counterpart comes to the regular world to take the dead-Lionel's place, he makes it clear that he wants Lex to carry on his legacy and be the heir to the Luthor "kingdom". He actually ousts his daughter from the exact position that he wants a Luthor heir in, because she's not his son. (Though her earlier Heel Face Turn might also have been a contributing factor.) Lionel is so obsessed with bringing his son back to take his place that he's also completely willing to kill said daughter to make it happen.
A subversion occurs in Farscape. The crew lands on a Sebacean breakaway colony where succession goes to the eldest child regardless of gender but the law states that a husband and wife must rule together. As such, the princess cannot become empress unless she finds a male who can give her children before she reaches a certain birth day (and, due to some gene poisoning by her brother, only Crichton fits the bill.)
Subverted in William Shakespeare's The Winter's Tale. His courtiers want Leontes to remarry, to provide an heir, but the oracle had said that he would live without an heir unless his lost daughter was found, and so he refused.
In Anne of the Thousand Days, a play by Maxwell Anderson about Anne Boleyn and Henry VIII, Anne promises to give Henry "boys in plenty" if and only if he makes her his queen. When Anne has a daughter, she becomes determined to have Elizabeth succeed him as queen. Henry agrees to order the necessary murders on the condition that she give him a son—which she proves unable to do.
Gender inverted: The dual office of Empress and Apostle of Begnion in Fire Emblem: Path of Radiance and Radiant Dawn. The two offices are inadvertently separated when the first-born female of the current generation is thought to have been assassinated, leaving an Empress who cannot hear the Goddess's voice. The true apostle isn't dead, though.
Gender inverted: the Fey Clan in Ace Attorney values females over males because only women can be spirit mediums. This means that if a couple has a daughter, the father gets pressed out of the light from both directions. End result: Kurain Village, home of the Fey Clan, has an extremely disproportionate divorce rate for its size.
Gender inverted... Again: In Suikoden V, the country of Falerna is ruled by a royal house who practice female inheritance of the throne. The Queen rules the country and takes a male consort (decided by an Inevitable Tournament between the country's various noble houses and other competitors), who becomes commander of the country's armies and Knight Commander of the Queen's royal knights. The main character, who is the eldest-born prince, has no right of succession and is groomed to becoming a statesman or a general in the armies, while his younger sister is groomed to be Queen.
Persona 4 has the odd example of Naoto Shirogane. As a female born into a long family of detectives she's convinced that she'll never be able to continue the family tradition as a girl and tries to pass herself off as male until she's exposed. Interesting this seems to be all in her head and not her family's view at all. We never meet her grandfather, only one of his servants, but from the message he delivers it's clear he has no doubt that his granddaughter will make a fine detective and in fact was concerned that she wasn't being true to herself by faking being male.
In The Witcher 2, one of the triggers that start the events of the game is that king Foltest has a lack of proper male heirs: He has a bastard son, who is still technically higher on the succession line than Foltest's acknowledged daughter (though said daughter is also his niece, which possibly explains that part). The poor boy is assassinated halfway through the game, leaving his other sister (Foltest's youngest, a bastard daughter) as heir incumbent. Geralt's actions may end up helping to legitimize her claim.
An integral part of Sengoku is ensuring you have male heirs. If you don't, and your clan leader dies, you lose.
In World of Warcraft, it' sindicated that Magni was disappointed because his only child Moira was not a male heir. As a ressult, Moira became quite bitter, and eventually fell in love with the Dark Iron Dwarves' emperor, before returning to Ironforge to claim her throne after her father turned into diamond in a ritual gone wrong.
Crusader Kings 2 has three gender inheritance laws. Agnatic inheritance only allows men to rise to power, Agnatic-Cognatic allows women to inherit if there are no valid male inheritors (but still prefers women with male issue to ones without), and Absolute Cognatic is gender-neutral (but can only be enacted if your ruler is of the Basque culture). However, if you pick a less traditional inheritance law (such as Elective Monarchy), it's possible for women to inherit fairly easily. Rulers with female heirs get a relation penalty to all their male vassals, as do all female rulers.
In The Royal Trap, succession works a bit differently: the ruler is the King, but the King is the man who marries the firstborn princess. This means that a realm needs to have a female heir; princes are sent wife-hunting. Because of this, when the real Princess Cassidy died, her parents had a farmakeist transform her brother Caspian into the new Princess Cassidy and cover everything up. However, the new Cassidy cannot produce an heir; in one ending, the player character ends up in a threesome with Cassidy and Prince Nazagi so she can bear Nazagi's heirs, which will be passed off as Cassidy's.
Galasso in keeps trying to get people to breed with his daughter Conquest, even though she is a decent heir herself. What's particularly weird, as Conquest points out, is that Galasso has some weird inability to tell the difference between males and females, so his chauvinism is based on labels that he doesn't even understand.
Connie also mentioned to Ethan (after they had sex at Galasso's command) that she was "on the pill", indicating that she may be a bit more assertive than she lets on. She eventually gets sick of this and starts her own business, which appears to be more successful than Galasso's own.
Gender inverted in Drowtales due to a matriarchal society. Thanks to an injury from an enemy, Quain'tana has been unable to produce a suitable female heir for her clan despite having several daughters. The first hates her and mingles freely with the enemy, the second is possessed by a demon, and her adopted daughter was disowned after being tainted and generally considered a failure. She eventually resorts to stealing her eldest daughter's first child to solve this.
Girl Genius: The need to produce a suitable heir to the title of Storm King was central to the plans of the Knights of Jove to reclaim Europa (due to the fact that the Fifty Royal Families care a great deal about succession as security to their power; the Sparks aren't really all that bothered about it). Gil guesses that it was complicated by a long line of fops, idiots, madmen, and women. Apparently, Lucrezia Mongfish solved their problem with the aid of genetic engineering.
This seems to be the reason (or at best one of the reasons) the Erlkönig tries very hard to reconnect with his only son Jareth despite having an older daughter in Roommates. Made harder by the facts that the boy hates his guts for abandoning him, already founded his own kingdom and the king has some very strange ideas about how to do reconnecting ("An Offer You Can't Refuse", to date he could).
Gender-Inverted in W.I.T.C.H, where succession to the throne of Meridian/Metamoor is traditionally female, which is why the younger Elyon Brown is the rightful heir to the throne, over her older brother, Prince Phobos. Then again, considering he probably killed their parents, that's a good thing.
Daria has this as a minor plot point: Andrew Landon all but admits that after raising two girls, his infant son Evan is his favorite. Unfortunately, he seems to have divided up the "heir" duties so that Evan will become a football player, while Jodie still has to slave in her school work.
Absolutely Truth in Television throughout most of history, and in much of the world. You were an unfortunate queen if you couldn't bear a son — if you were lucky, the king wouldn't set you aside. Otherwise, you'd end up divorced, beheaded, poisoned, locked up in a convent, etc. Princesses becoming queens regnant (ruling queens) had all sorts of problems. No one wanted a female ruler, because if she married her kingdom would, most likely, be combined with that of her husband.
Examples from Europe:
Five European countries have done away with this altogether: Sweden, the Netherlands, Norway, Belgium, and Denmark. In other words, these countries provide that a woman can inherit the throne even if she has younger brothers (sometimes known as "absolute primogeniture"). The first of these changes was passed in Sweden effective January 1, 1980, and so far no woman has actually inherited a crown via absolute primogeniture; Sweden's Crown Princess Victoria is likely to eventually become the first woman in the modern world to inherit a crown despite having a living brother.
Of the other European countries that still have monarchies, Spain and Monaco have succession laws like the UK's male-preference primogeniture (younger brothers inherit the crown before their older sisters). Luxembourg and Liechtenstein follow what's known as "semi-Salic law", in which a woman can only inherit the crown if the entire royal family runs out of male heirs, including her own sons. Another once-common succession law was the "Salic law" (the non-"semi" version), in which only male descendants in male line could inherit the crown at all; this was applied in France and some other countries, but none of the extant European monarchies still follow it (on the other hand, Japan does).
The Disunited Kingdom:
It was this issue that started a period in English history known as The Anarchy, when Henry I named his lone surviving child, Matilda, his heir. It was a bit more complicated, in that not only were the Anglo-Norman barons wary of having a woman on the throne, but her husband was from Anjou, Normandy's rival. A faction of barons helped Stephen of Blois onto the throne, which plunged England into 19 years of civil war until a resolution was reached where Stephen's own sons would be bypassed for succession in favor of Matilda's son, the future Henry II, who was the founder of England's Plantagenet dynasty, which of course produced some of England's most famous kings, like Richard the Lionheart, Edward I 'Longshanks', and Edward III.
Matilda's son Henry II profited from this when French king Louis VII grew so worried over his wife Eleanor of Aquitaine so far only bearing daughters that he had his marriage annulled (officially on grounds of consanguinity) even though that meant losing control over Aquitaine. To make matters worse from Louis' point of view, Eleanor then married Henry II (handing over Aquitaine to England) and bore him four sons, including Richard the Lionheart and John. Of course from Henry Plantagenet's point of view that may have been too much of a good thing because his sons kept conspiring and fighting against each other as well as against their father.
Henry VIII of England divorced his first wife because of this. He even went so far as to reject the Roman Catholic Church because they wouldn't let him get his marriages annulled. He had some justification — his father was an upstart who'd taken the throne after a long civil war, and he couldn't be sure a daughter would be accepted. To make matters worse, enemies could make a very good case that each of his daughters was illegitimate — and in the case of Elizabeth, that she wasn't even his daughter. See The House Of Tudor for more on him and his family, including Elizabeth I.
In a clever compromise to get around this trope, the later Mary II married her cousin William of Orange, a Dutch duke, and they were appointed as equal co-monarchs. This was seen as the best of both worlds: William was the first male in line to the throne in his own right, and despite being a foreigner he was more importantly at the time a Protestant; meanwhile, Mary was a woman, but she was also a direct descendant of the established dynasty; as a bonus, it also seems to have been a Perfectly Arranged Marriage. The only minor hiccup was that Mary's father James II was still alive at the time, and being deposed for Catholic sympathies. (Ultimately, William and Mary had no surviving children, so after they both died Mary's sister Anne succeeded them, ruling in her own right.)
The Kingdom of Hannover was once in a personal union with the United Kingdom, but they followed the Salic Law (forbidding women to take the throne) while Britain did not; this caused a split when Victoria became Queen (her uncle Ernest Augustus became King of Hannover instead).
The House of Hapsburg lucked into Castile/Aragon/Burgundy/the Low Countries because the Houses of Valois and Trastámara married a princess into their dynasty and failed to pop out a male heir. To avoid being on the receiving end of this the two branches of their house swapped most of their princesses between the Spanish and Austrian courts. The long term effects of this policy◊... did not work out too well for the Madrid branch, and the male line of the Vienna branch puttered to a halt not long afterwards with predictable results (luckily for them, the people who ended up the heirs were content to call themselves Habsburgs).
Maria Theresa of Austria had her father's approval but not anyone else's. When a series of unfortunate events killed all available male heirs, her father issued a pragmatic sanction that left the Habsburg domains to her. He paid many rulers to accept it and not contest her claim to the throne once she would succeed him. Of course, when he did die, many thought this was a prime opportunity to go back on their word and grab some land. It mostly didn't work out (Silesia was lost to Prussia, the Habsburgs almost gained Bavaria, but otherwise Maria Theresa went on to rule the Habsburg domains for 40 years).
France through history:
The Frankish Salic Law that prohibits females from inheriting noble titles in their own right dates from the 6th century, although until the ende of the 14th century it applied only to the inheritance of property. It was first invoked with reference to the succession to the throne in the 15th century, half-way through the Hundred Years' War. In the succession crises after the deaths of Philip IV the Fair and his youngest son Charles IV the Fair, the French greats and their legal experts had excluded females from the succession without mentioning the Salic Law. In both cases, other aspects — a notorious case of marital infidelity on the part of several princesses and the fact that the greats of France did not want an English king — played a part. Up until Charles IV the Capetian kings and their queens had, almost incredibly, always managed to produce one or more male heirs in every generation.
When France still had a monarchy there were laws against women inheriting the throne. It wasn't that the French considered women unfit to rule — women acting as regents was permissible, as shown by the example of Blanche of Castile, who ruled France during the minority of her son Louis IX (Saint Louis) and also during his absences for his two Crusades. It was just the contention of French lawyers and theologians that the French King was too holy and sacrosanct for that office to be held by a woman.
In ancient Rome, if you weren't able to produce a biological heir, adopting one worked just as fine. In fact, the majority of Roman emperors inherited the empire after having been adopted by the previous emperor. Some even disregarded their biological children in favour of an heir of their choosing. Julius Caesar, for example, had a son by Cleopatra, but chose to adopt his sister's grandson as his firstborn son and made him his heir instead. This adopted son later became known as Emperor Augustus, who in turn adopted his wife's first son (fathered by her previous husband) as his heir. This proved to be a smart tactic, as often the person who seemed best suited to take over the empire would be adopted by the emperor, instead of trusting that pure biology would make someone a great leader.
As of 2011, The Commonwealth has begun the process of changing to equal primogeniturenote and also removing the bar on those who had married Catholics to succession to the throne; however, the requirement that the monarch be a Protestant has not been removed, as he or she will continue to be the Supreme Governor of the Church of England and the Prime Ministers of the Commonwealth Realms have all agreed in principle to the modification. However, as the Commonwealth monarchy is governed by separate but identical laws in all the Commonwealth Realms, the change requires parliamentary approval in all Realms save New Zealand and Papua New Guinea. Canada creates further problems: it will require the approval of all ten provincial parliaments, as well: the provinces are legally distinct monarchies, so their separate but identical laws would also need to be changed. Some fear that Quebec might hold up the process as a means of getting long-desired concessions from Ottawa, particularly now that the sovereigntist Parti Quebecois is in power.note Theoretically, the six Australian states will also need to approve the changes separately, but as Australia doesn't have any serious separatist movements, this is a nonissue.
The Unfortunate Implications of China's One Child Policy is that, since families want male heirs, they've been having (or keeping) too many sons and not enough daughters, which means not enough wives to go around (which anyone could tell you is what happens when it's only acceptable to have sons!). Oops! The government eventually had to compromise by allowing girls to inherit their family name and giving families "incentives" (read: money) to have baby girls.
India has not been immune to the same pressures: despite the absence of a policy requiring that families limit their size, increasing prosperity and a government awareness campaign on overpopulation have caused many Indians to want to limit the size of their families (typically 2-3 children). However, the traditional attitudes remain, and many Indian women selectively abort female children, although this is technically illegal. While the gender ratios in India are nowhere nearly as skewed as in China, it is a problem that the Indian government is taking quite seriously.
In Japan, there was a decades-long controversy about there not being a suitable male heir to inherit the imperial throne, to the point that a constitutional amendment was in the works to allow at least partial female inheritance. Fortunately(?) Princess Akishino gave birth to a boy, meaning that the question was staved off for at least another generation. The Crown Princess was not seen in the public after 2002 to seek treatment from adjustment disorder with her husband Crown Prince Naruhito issuing statements that he's concerned with the health of his wife. The remarks unfortunately earned the crown prince rebukes from Emperor Akihito and Prince Akishino while the comments became part of the debate on whether females can really ascend the throne.
In Russia Peter I the Great had set down a house law that monarchs could appoint their own successors, as a consequence of which his throne was first inherited by his widow Catherine I and which probably contributed to the succession being settled by palace coup a number of time during the 18th century. After a period that saw three more ruling Czarinas, Czar Paul I, who bore a grudge against his mother Catherine II the Great for deposing his (supposed?) father Peter III and allowing him to be murdered, then enacted a new house law that henceforth excluded women from the succession.