There was a war. It happened years ago, maybe even thousands of years. Characters reference it, especially if they took a part in it: the ShellShockedVeteran never managed to get over what he experienced back then, while the PhonyVeteran, on the other hand, will never shut up about how many brave things he did in it.

Sometimes people will use the war as a reference point for placing events on a timeline - something happened a few years before the war, or somebody did something after the war.

Maybe people still have to deal with its consequences. The war happened, and it left its ugly mark on the world. But it's [[TakeOurWordForIt never shown to the audience]] - we never see a single {{flashback}} from the war, are never shown more than just a glimpse of what happened. The war will be referenced, but otherwise left mysterious, unexplained. Why it happened, how it ended, and what all the things that took place there (which people talk about [[CrypticBackgroundReference like it should be obvious]]) actually were, are never explained. The war is only a mysterious event of the past, included mostly to add a bit of mystery and [[WildMassGuessing give people excuses for insane ideas]]. Needless to say, this trope can easily be processed into FanficFuel

WorldWarThree is often used as this, as are [[WorldWarWhatever the Fourth, Fifth, Sixth and so on]]. For that matter, so are the First and Second. Stories set AfterTheEnd have the tendency to do this with the war that caused the apocalypse. If the war never stopped, may be a ForeverWar.

If said war is going on presently but the characters themselves aren't involved, then it is BehindTheBlack.

Often used as a sub-trope of CrypticBackgroundReference. Compare also CataclysmBackstory.

Please, avoid shows referencing RealLife conflicts. We already have plenty amount of information on them.
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!!Examples:

[[foldercontrol]]

[[folder:Anime and Manga]]
* The ''GhostInTheShell'' TV series is set sometime after both WorldWarIII ''and'' IV.
* ''Anime/CodeGeass'' has the Britannian invasion and conquest of Japan, which we see only in flashbacks concerning young Lelouch, Suzaku and Nunally and the one from first episode opening sequence. There also was an alternate version of the Napolean wars, where Napoleon conquered Great Britain, making all the British aristocracy run to America, creating the Britannia Empire.
* The many wars of the Ancient Belka in ''LyricalNanoha''. We have been told some general info about it, such as how it destroyed Old Belka and [[YearZero led to the current age]] where physical-based weapons were banned, but otherwise, it's a big question mark. As ''NanohaViVid'' revolves around the {{Reincarnation}} of two prominent figures from that war, many readers hope that it will eventually give more insight to that period.
* ''Anime/CowboyBebop'' has the War on Titan, which shaped the lives of Spike, Vincent, and Grencia years before any action related to the main story took place. We get a few glimpses of it in flashbacks however.
* ''LastExile'' also has the war between its two major powers, which is mediated by The Guild. Much of the action of this war takes place BEFORE the actual story, as a few episodes in we discover that [[spoiler: one of the planets these factions live on is dying, essentially taking them out of the conflict for good. They're pretty much refugees after this point.]]
* In ''BlueGender'', we don't actually see humanity get overtaken by the Blues.
* The War with "Them" in ''SoraNoWoto'' is a complete mystery that has become filled with myths.
* Mysterious conflict with MazinkaiserSKL, whose conseqences are related to events of the series.
* ''Manga/{{Naruto}}'' has the first three Shinobi World Wars; though they play a major role in the backstories of a good chunk of the main cast, we still know very little about these conflicts outside of a few offhand mentions and short flashbacks, plus a single gaiden story starring Kakashi.
* The war between [[TheFederation Megalomesembria]] and [[TheEmpire Hellas Empire]] in ''MahouSenseiNegima''.
* ''PumpkinScissors'' begins with the graduation ceremony of a class of army cadets being interrupted by an announcement that the war everyone thought they were going to be sent to fight in had just ended. The series itself is about a team working to help repair all the damage that was inflicted on their country during the war.
* The war between the [[spoiler: Spiral Warriors and the Anti-Spirals]] in ''Anime/TengenToppaGurrenLagann''. Parallel Works #8 details this a little focusing on Lordgenome's involvement.
* In ''Anime/NeonGenesisEvangelion'' several wars broke out a few days after the Second Impact, one of which resulted in the destruction of Tokyo. We know nothing about these wars other than what's mentioned in [[http://wiki.evageeks.org/Second_Impact Shinji's history textbook]].
* The war with the Quincies in ''Manga/{{Bleach}}''.
* In ''SuperDimensionFortressMacross'', the backstory tells of a massive war between the Zentradi and a group known as the Supervision Army. The war ended long ago, and Britai's force is conducting mopping-up operations when they come across the Macross. The storyline is carried into ''Macross7'', where we get some understanding of what the Supervision Army was, but the war itself is still an offscreen event.
** There is also a WorldWarIII fought on earth, that leads to a OneWorldOrder. Though a prequel ''MacrossZero'' covers some characters actions in it, most of the factions and causes are kept vague.
* Heavens War in ''DarkerThanBlack'' serves as the backstory for most of the main characters, and is the driving force behind Hei's actions [[spoiler: his sister Pai disappeared at the end when Heavens gate exploded, and Hei is trying desperatly to find her.]]
* ''Manga/NausicaaOfTheValleyOfTheWind'' has the Seven Days of Fire, in which the God Warriors were unleashed on the world and industrial civilization was destroyed.
[[/folder]]

[[folder:Comic Books]]
* In the second arc of ''TheAuthority'', Jenny Sparks mentions how Earth cut down all connection with the alternate Universe, The Sliding Albion, after the First World War erupted there. Characters from Albion mention briefly that between that event and Albion's invasion on Earth, that world has seen ''eight'' other world wars.
** Also, the fourth story arc (and first written by MarkMillar) showed us a glimpse of another alternate Earth, which had thirteen continents. A world war that erupted there ended with armies of [[AdolfHitler Ado]][[CompositeCharacter lf]] [[MalcolmXerox X]] exterminating all non-black people on ''all'' of them. The Engineer finds the idea of sending a group of superpowered white supremacists there quite interesting.
* Venado Bay in ''ComicBook/{{Legion of Super-Heroes}} V4''.
* ''StarWarsLegacy'' has the conflict between Galactic Republic and Empire, won by the latter, who then got into the war with the Sith.
[[/folder]]

[[folder: Fan Works]]
* The Private War in ''Fanfic/TheJacksonLegacy'' takes place a decade before the story kicks off.
* In ''Fanfic/WithStringsAttached'', Grunnel talks about how the Tayhil and their monsters conquered most of Baravada some 200 years ago, and how the skahs rose up to take back the place.
* ''FanFic/ThePowersOfHarmony'' has the War of the Sun and Moon, the conflict between Celestia and Nightmare Moon, which in this story is presented as having lasted several years. There are a few flashbacks to it, but for the most part it's offscreen.
* ''FanFic/ToTheStars'' has the Unification Wars between the United Front and Freedom Alliance. Most of the details are AllThereInTheManual.
* ''FanFic/QueenOfAllOni'': The Red King's Rebellion, wherein Tarakudo overthrew the [[PredecessorVillain Oni Elders]]. We only see a portion of the FinalBattle, spread out over two separate flashbacks.
[[/folder]]

[[folder:Film]]
* When watching ''{{Airplane}}'', they never make clear which war "The War" was for Ted Stryker, though judging by when the movie was made, one might assume Vietnam. As farcical as the entire movie is, it could very well have been some other war entirely though. Hell it could be a war they (or Ted) completely made up as well.
** "The War" in ''ZeroHour!'', the film on which ''Airplane!'' is based, and which came out a quarter of a century earlier, was obviously WorldWarII. This timeframe informs a lot of the gags and references in the latter film.
* ''Film/TheLordOfTheRings'' begins with Galadriel recounting the story of the last war with Sauron, several thousand years prior. We only see the end of the final battle.
* The Clone Wars were this for the ''StarWars'' trilogy until the prequels came, then two cartoons and a lot of other things that explored it, so it ultimately avoids this trope.
* ''[[Film/TheTimeMachine1960 The Time Machine]]'' (1960): In-Universe. The protagonist from 1899 traveled a couple of decades into the future. One of his friends' sons mention "the front" of "the war". It's obvious its the First World War, but being a time-traveler, he was unaware.
[[/folder]]

[[folder:Literature]]
* The ''Literature/{{Discworld}}'' series has two examples - the wizard wars which serve as an example of why wizards shouldn't actually cast spells, and the wars of the Evil Empire, which serve as the origin story of the Orcs. The latter may or may not be the same as the "big old wars" mentioned in "Troll Bridge", in which Cohen the Barbarian fought for a bright new future and the [[ShoutOut return of the king]], and Mica the troll fought because a big troll with a whip told him to.
* The First Wizarding War against Voldemort in the HarryPotter books.
** The war against Gellert Grindelwald is even more obscure. All we know for sure is that it apparently took place around the same time as World War II. Fanon consensus is that Grindelwald and ThoseWackyNazis had some sort of alliance.
* Twice in ''Literature/TheHungerGames:'' the [[AfterTheEnd civilizational collapse]] that led to the founding of [[PoliceState Panem]], and the more recent "Dark Days" when Panem's provinces rose in an unsuccessful rebellion against the Capitol.
* Creator/WilliamShakespeare's ''AsYouLikeIt'': Duke Senior was (somehow) deposed by his younger brother Fredrick and exiled to the Forest of Arden. A very blatant DeusExMachina at the end restores Senior to his rightful place.
** Also Old Hamlet's war with Norway in ''{{Hamlet}}''.
** Theatre/{{Othello}}'s military record might also count: he boasts at length of his experience with 'pride, pomp and circumstance of glorious war', but we never see him fight.
** ''Theatre/{{Macbeth}}'' begins with a recounting of a war between Scotland and Norway.
* The [[http://en.wikipedia.org/wiki/Butlerian_Jihad Butlerian Jihad]] is repeatedly mentioned in the original ''{{Dune}}'' series and had a profound effect upon the setting. [[FranchiseZombie After Frank Herbert's death]], his son Brian and Kevin J. Anderson wrote a prequel trilogy to flesh out the details. [[FanonDisContinuity But the fans try not to talk about those.]]
** Besides the war, the trilogy also serves to [[AssPull conveniently]] set up most of the major players in the original ''Dune'' [[TheVerse 'verse]], such as the [[TheEmpire Corrino Imperium]], the House of Atreides, the House of Harkonnen, the Spacing Guild, the Bene Gesserit, the Suk Inner School, and the mentats.
* Bujold's ''Literature/VorkosiganSaga'' is full of these. Mad Yuri's War, the Cetagandan Invasion, the Komarr Conquest and subsequent Revolt all have a direct impact on the storyline decades after they took place.
* The [[AlienInvasion Psychlo invasion]] in ''Literature/BattlefieldEarth'', which lasted about [[CurbStompBattle 9 minutes]].
* In SergeyLukyanenko's ''[[Literature/NightWatch Watches]]'' books, the Treaty is signed between the Light and the Dark Others after a magical war that nearly destroyed everything. Hardly any details are revealed about the war. The beginning of TheFilmOfTheBook ''Night Watch'' shows a battle between two groups of barbaric-looking people without using any magic (the director hates magic), with each group consisting of two dozen men at most. This is likely meant to be [[WhatDoYouMeanItsNotSymbolic symbolic]], though.
* LarryNiven's ''Future History'' (leading to KnownSpace) series deals heavily with relations between humans and the Kzin, but the early Man-Kzin Wars never showed up in the books just because Niven didn't like writing war stories. He did let other writers go back and fill that in later, though.
* The aptly-named Vague War in SergeyLukyanenko's ''LineOfDelirium'', which takes place decades prior to the novel. Many references are made to the war, but few details are revealed. Apparently, it was a big free-for-all with all known races but no alliances. The war led to the formation of the [[TheEmpire Human Empire]]. The author even throws in a funny story about humans spreading misinformation about their dietary needs (i.e. that we need spinach to survive). The aliens spend resources developing a spinach-killing virus and lose countless ships spreading it throughout the human worlds. When humans don't die, they [[OhCrap surrender out of shock]]. On a less funny note, good luck finding spinach after the war.
* The Aiel War in ''Literature/TheWheelOfTime'' is mentioned in passing by numerous veteran Warders, Tam al'Thor, and others. Many other wars - the Breaking of the World, the War of a Hundred Years, Artur Hawkwings war of consolidation, all serve to create rich background for the series.
** The ending at least of the Aiel War was covered in the {{Prequel}} novel, ''New Spring.''
* In [[SwordOfTruth The Sword of Truth]] series, many of the {{MacGuffin}}s, events and plots of the entire series are a result of the direct influence of the events in the Great Wizard War that happened over 3000 years ago.
* ''ASongOfIceAndFire'' has many of these. The most important is Robert's Rebellion, which is really the cause for all of the events in the series - giving the effect that the reader has plunged into [[InMediasRes the middle of the story]] rather than the beginning. More recently, there was Balon Greyjoy's Rebellion. Further back in time, we had the Targaryen Conquest, the Blackfyre Rebellion, and the War of the Ninepenny Kings. Going even further back then that, back to mythic times, there are the stories from various cultures about a great battle between good and evil, implied to be an ealier war with [[BigBad The Others.]]
** Also, whatever it was that Tywin Lannister did the to inspire 'The Rains of Castamere'. "But there are no Reynes and Tarbecks"... "Exactly."
* From ''Literature/HonorHarrington'':
** Admiral Theisman's purge of the StateSec forces which refused to fall in line with the new government after the overthrow of the Committee of Public Safety. The only part of it shown is from ''The Fanatic'', which itself took place away from the meat of the action. Not a typical example, as that particular conflict took place between two of the later books of the series.
** Earth's "Final War" many centuries before the current timeline, where the planet was nearly rendered completely uninhabitable until several colonies sent aid to repair the damage.
* In Creator/JoWalton's AlternateHistory ''Literature/SmallChange'' trilogy, Germany continued fighting on the Eastern Front past 1949; Japan conquered most of China. The novels take place from the detached perspective of England, with word of the continuing war coming in [[CrypticBackgroundReference newspaper headlines and occasional chatter]].
* Creator/StephenKing's ''Franchise/TheDarkTower'' series occasionally reference the last war of the Gunslingers against the Good Man, and it's the backdrop against which ''Literature/WizardAndGlass'' is set. There is also an even older event implied to be a nuclear war, which is why the series is AfterTheEnd in the first place.
* In the StarTrekNewFrontier series, Calhoun and Picard (and their crews) discover that a species that's apparently been friendly is actually capable of an insidious level of mind control which they've hid successfully until then. In the next book in the series, there's been a TimeSkip of several years and said alien species has been defeated after a fairly vicious war.
* ''[[Literature/{{Lensman}} Triplanetary]]'' mentions the first and fourth Jovian Wars, which resulted in the formation of the Triplanetary League from Venus, Tellus, and Mars.
* The 'Holy War' against the Ghouls in E. R. Eddison's ''Literature/TheWormOuroboros'', in which all the civilized ("polite") nations of the world of Mercury fought alongside each other, and that ended just shortly before the book's storyline begins.
* In ''Literature/NineteenEightyFour'', there is supposedly a vast war raging between the three superstates, but it has no actual bearing on the novel's plot. [[spoiler: Of course, it could just be made up to make the party's rule seem legitimate]].
* Some kind of great war is implied to be happening in LordOfTheFlies. The reason the children are on the island is because the plane that was evacuating them from an imminently about to be nuked Britain was shot down.
[[/folder]]

[[folder:Live Action TV]]
* The Last Great Time War from ''Series/DoctorWho''. It was never shown, we know only that it caused a lot of destruction and wiped out entire races, including the Time Lords, whose last survivor was the Doctor. We find out that the Doctor was the one who ended the war, killing ''every'' Dalek (apart from [[JokerImmunity a few who got away, of course]]) at the cost of also killing ''every'' Time Lord, including his own children and grandchildren. The Doctor has to deal with the consequences of the Time War from time to time and sometimes he or somebody else makes a reference to some events of it, but it's still mostly a mystery.
** Current showrunner StevenMoffat has gone on record saying that he will never show the Time War since there isn't enough money in the world to do it justice.
-->'''Doctor:''' You weren’t there in the final days of the war. You never saw what was born. But if the Time Lock’s broken then everything’s coming through, not just the Daleks, but the Skaro Degradations, the Horde of Travesties, the Nightmare Child, the Could-Have-Been-King with his Army of Meanwhiles and Never Weres – the war turning to Hell.
** Older episodes referred to similar such events, including the survivors of the destruction of Phaester Osiris defeating Sutekh and sealing him in a pyramid on Mars, or the ancient war between the Time Lords and the Great Vampires shortly after the beginning of time.
** Ancient battles between the Fledgling Empires (including Gallifrey) and the Racnoss were mentioned in "The Runaway Bride".
** The Sontarans have been at war with the Rutan host for at least 60,000 years of the Whoniverse's timeline (mentioned in both ''Series/DoctorWho'' and ''TheSarahJaneAdventures''), and yet we've never encountered a Rutan and Sontaran together on TV once.
** PlayedWith in "The Doctor's Daughter". A war, fuelled by cloning machines, has gone on for 700 generations. It turns out that those 700 generations were cloned, shoved into battle and killed in the space of [[spoiler: one week]].
** The great Cyber-Wars fought between human forces and the Cybermen were mentioned frequently, but the Cybermen were hardly even seen at the height of their power - mostly after the fact as TheRemnant.
* ''Franchise/StarTrek'' has a lot of those.
** The Third World War and Eugenic Wars, all taking place on Earth and concerning only humanity. It was actually one war in the Original Series, but was later [[{{Retcon}} divided]].
*** There are [[ExpandedUniverse EU]] novels dealing with both, with ''The Rise and Fall of Khan Noonien Singh'' being the most prominent. Also, in the interest of reconciling the Eugenics Wars with the real life passage of the era in which they are said to have taken place (1990s), the Eugenics Wars were retconned into a far less grand scale war that happened mostly in the shadows of real life events.
** The war between the Federation and Romulan Empire, which forms the backstory for the episode "Balance of Terror".
** The ongoing war between the Federation and the Klingons at the time of the Original Series is mostly not shown.
*** Note that the Federation and the Klingons have gone to war many, many times: A few of these conflicts ''have'' been depicted on-screen, including in the Original Series: The brief Federation-Klingon War of 2267 (which was ended by the Organian Peace Treaty, imposed upon the belligerents against their will) took place entirely within the episode "Errand of Mercy". Another Federation-Klingon War took place during the first half of the fifth season of ''Deep Space Nine'', which was effectively ended (and the terminated alliance suddenly restored) when the Cardassians joined the Dominion.
** ''[[Series/StarTrekTheNextGeneration The Next Generation]]'' has the war between the Federation and the Cardassians, which was responsible for creating the Anti-Cardassian [[LaResistance Maquis]]. Strangely, it wasn't mentioned in the first seasons, only later.
*** The implication is that the Federation was pulling its punches more than a little. Their ''defensive'' action shook the Cardassian Union nearly to the point of collapse.
** In Film/StarTrekInsurrection, the [[Series/StarTrekDeepSpaceNine Dominion War]] is treated like this.
** As well as "brutal border wars" against the Talarians and the Tzenkethi, which happened at some point between the Original Series and the next Generation.
** The Earth-Romulan war ended as this, because ''[[Series/StarTrekEnterprise Enterprise]]'' was cancelled before it could cover it. The continuation novels have since stepped in to flesh it out.
*** When first mentioned in the original series, this war was fought entirely at extreme ranges with nuclear weapons (and with neither race ever actually seeing a member of the other).
* Both series of ''Franchise/BattlestarGalactica'' have mentioned previous wars with Cylons.
** However, the new BSG's First Cylon War will be getting screentime in the upcoming ''Blood and Chrome'' series. A licensed video game also purports to cover that period, even being played from the perspective of Commander Adama as a rookie pilot, but it mixes and matches so many elements of the original series and remake that it probably belongs in its own separate continuity.
* Silicate War, the war with the android revolution, taking place years before events of ''SpaceAboveAndBeyond''.
* The conflict between Dharma Initiative and the Others was only hinted at in the first four seasons of ''Series/{{Lost}}'', though the Season 5 gives us a pretty clear picture of it. The conflict between the Others and the US Army is even more obscure.
* The war with the Magogs from ''Series/{{Andromeda}}'', the end of which caused the [[NietzscheWannabe Nietzschean]] revolution, may count too, as it started at the beginning of the first episode. The episode then jumps 300 years in the future, to the main plot, not only skipping the downfall of the revolution, but also the civil war among the ones who caused it, the High Guard.
* Played with in ''ThatMitchellAndWebbLook'' where a group of people are holed up in a nuclear bunker playing a game show and broadcasting in the vain hope somebody is actually watching. It all focuses around "The Event"; the only interesting thing any of the characters can think about but are sworn not to talk about for various reasons. The most probable event would be a nuclear war.
** Or alternatively whatever caused the majority of the human population to become zombies ('Them').
* ''[[Series/BabylonFive Babylon 5]]'' has the Dilgar War, the first major interstellar war that the humans got involved in, as well as the previous Shadow War, which took place around a thousand years previously. We do see a glimpse of that era, mostly just some less advanced looking Minbari ships, but nothing of the war itself.
** Also the Telepath War. We are shown only before and after.
** And the first Narn war for independence from the Centauri, about 100 years prior to the beginning of the series.
** Along with the numerous wars the Centauri Republic was waging with its neighbors in the third season, none of which are seen, or indeed the numerous smaller wars between the members of the League of Nonaligned Worlds in the same season.
** There are also allusions to various minor conflicts that the Earth Alliance took part in. Not to mention the Earth Minbari War, which we heard much about, but saw little of, until the prequel movie ''In The Beginning''.
* ''Franchise/PowerRangers'' falls back on this one a lot, to the point where EpilepticTrees have grown due to some wars sharing the same rough dates. Some of these conflicts are original while others are carried over from the original ''Franchise/SuperSentai'' counterparts:
** ''Series/MightyMorphinPowerRangers'' had a great battle between Good and Evil 10,000 years ago. Zordon was with the good guys, Rita with the bad guys under the command of Zedd. We have no other clues about it beyond that, despite the ''many'' ancient magical characters who were there and make none-too-informative references to it.
** ''Series/PowerRangersLostGalaxy'' is so vague that we don't even know if there was one big event or just a bunch of isolated incidents. Either way, a lot of backstory happened 3,000 years ago.
** ''Series/PowerRangersLightspeedRescue'' had Bansheera and company [[SealedEvilInACan put in the can]] 5,000 years ago. Her ''entire'' motivation for attacking in the present is to destroy the city and reestablish her palace upon the demons' sacred ground, granting 'ultimate power.' The fact that she had it then meant she had to have been a lot worse than anything witnessed during the Lightspeed series.
** ''Series/PowerRangersWildForce''/''Series/HyakujuuSentaiGaoranger'' had the war between the Animarian civilization and the Orgs 3,000 years ago.
** ''Series/PowerRangersNinjaStorm'' introduced one of the generals this way; the warlord Shimazu terrorized the populace with his Wolfblades 2,000 years ago until he is sealed in a mask.
** ''Series/PowerRangersMysticForce'' saw a group of wizards seal away the forces of the underworld only twenty or so years prior.
** ''Series/PowerRangersJungleFury'' had a war between man and beast 10,000 years ago. Surprisingly, the four of the seven {{Old Master}}s that survived the war also survived to the present day.
** Averted in ''Series/PowerRangersRPM'', where we get a number of flashbacks to Venjix's conquest of Earth the year prior.
** ''Series/PowerRangersSamurai''/''Series/SamuraiSentaiShinkenger'' had the Nighlocks/Gedoushu sealed away by samurai in feudal Japan, and apparently a number of skirmishes between them and the samurai's descendants in the intervening years.
** Gloriously averted with the Great Legend War of ''Series/KaizokuSentaiGokaiger'', though the [[TheEmpire evil Space Empire Zangyack]] are said to have had a long history conquering the universe before the invasion of Earth.
* In ''Series/TheWalkingDead'', the military is mentioned to have been overtaken by the [[OurZombiesAreDifferent Walkers]] and their abandoned equipment and corpses are seen lying about in the streets of Atlanta and outside of CDC, but it's never shown how the military were defeated.
* The ''Series/{{Firefly}}'' pilot (and one other episode) contain a flashback to the "Independence War", but other than that it's just talked about, although its aftermath is the prime motivation for many of the characters.
* ''KamenRiderAgito'' is a non-direct sequel to ''KamenRiderKuuga'', most explicitly referenced by the police-made G3 PoweredArmor being based on data from Kuuga himself. According to the backstory, Kuuga's old enemies the Grongi fought a war against another monster group, the Lords, who eventually won and became the villains of ''Agito''. ''KamenRiderDecade'' directly references this when the heroes go to an AlternateUniverse version of ''Agito'' and land right near the end of the Grongi-Lord War.
** And of course then there are things like the Rinto Kuuga's battle with the Grongi, the [[KamenRiderBlade Battle Royale]], and [[KamenRiderOOO the original OOO's battle with the Greed]], though that one is not what it seems.
* In ''Series/{{Merlin}}'' there are increasingly frequent mentions of a war waged at some nebulous time before/around King Uther's time in which ancient/recent kings were pitted against the sorcerous High Priestesses.
* The Makhash Wars from ''Series/BuffyTheVampireSlayer''.
* ''Series/{{Scrubs}}'' has the Janitor mention overthrowing Kyle, the former leader the Brain Trust ("A dictatorship masquerading as a democracy") during The Revolution of '02, specifically The Battle of the Basement Supply Closet. [[UnreliableNarrator This probably never happened.]]
[[/folder]]

[[folder:Multiple Media]]
* The Core War in ''Franchise/{{Bionicle}}'', although we do see a very brief account of its more important moments in one of the {{Flashback}} comics.
[[/folder]]

[[folder:Tabletop RPG]]
* ''DungeonsAndDragons'' adventure I12 ''Egg of the Phoenix''. The War of Ending between the forces of Evil and Old Empyrea. Doc and the silver dragon Falx fought in the war, during the adventure the {{PC}}s find a message that dates back to it, and one mission involves scouting one of the Castles of Ruling that played a major part in the war.
** The PointsOfLight settings in 4th Edition has the war between the civilization of Nerath led by King Elidyr and the gnoll demon horde headed by Yeenoghu. There was also the war between the tiefling (half-devil) empire of Bael Turath versus the dragonborn empire of Archosia. [[DungeonCrawling Your characters most likely will start their career scrounging leftover supplies from said wars.]]
** An attempt was made to rework the World Of Greyhawk setting with The Greyhawk Wars (the war Iuz was preparing for in the time period of the original boxed set). The war itself was represented as a stand-alone board game only. It produced some interesting novels set in the aftermath of the War where characters often have to deal with the consequences, but the canon version of the war itself is relatively obscure.
* ''{{Exalted}}'' has a few examples: the Primordial War, the Aftershock War, the Usurpation and the Balorian Crusade. All of these are provided some level of detail (specifically who was fighting and why), but the exact events of the wars are generally shrouded in mystery (typically because they all involved reality being damaged to some degree).
** And those are just wars involving the Exalted. The occasional hint is dropped regarding wars waged by gods in the era before humanity, and even occasionally to conflicts involving the Primordials prior to the existence of Creation.
** Autochthonia has its own version in the Elemental War (so named because it so devastated the mechanical ecology that it drove thousands of elementals violently mad), which was noteworthy for being an extremely violent, ethnically driven total war in a world where most fighting is skirmishes to steal resources and supply lines.
* ''TabletopGame/{{Warhammer 40000}}'' includes a lot of this in the {{backstory}}, such as a RobotWar that explains the Imperium's distrust of ArtificialIntelligence.
[[/folder]]

[[folder:Video Games]]
* ''{{RuneScape}}'' has the God Wars which had raged on for 4000 years, making up the entirety of the Third Age. Despite ending 2169 years ago, the repercussions are still felt today: many races are driven to extinction, down to LastOfHisKind or is a DyingRace; the gods are forced to depart from Gielinor. Many quests focus on this time: the Cave goblin-dwarf railway is postponed due to the discovery of related artifacts, the player rediscovers the myriad, a DyingRace of EnergyBeings, human-vampyre tension runs high but if another war breaks out, [[AllPowerfulBystander Guthix]] would be reawakened to [[TheEndOfTheWorldAsWeKnowIt destroy the world and remake it]].[[spoiler: Except now he's dead.]]
* ''VideoGame/{{Castlevania}}'' has "The Demon Castle War" in 1999 where modern-day soldiers attacked (and died; given the zombies) Dracula's Castle. This war also heralded Dracula's true and final death. There is no game that covers this.
* ''{{Freelancer}}'' has the [[TheEmpire Coalition]] / [[TheAlliance Alliance]] war, the beginning of which was shown in ''{{Starlancer}}'' but which lasted for another century afterward and the winner is not the one the first game would indicate, as well as the 80 Years War between Rheinland and the [[NGOSuperpower GMG]].
* ''Franchise/StarWars KnightsOfTheOldRepublic'' has the Mandalorian Wars. Much of the information about it is from allusions and AsYouKnow statements in the games, and lots of characters you run into in both games are war heroes or veterans from one side or the other.
* For the longest time, ''StarCraft'' had the Guild Wars, which were referenced only in vague snippets as a civil war whose consequences still loomed over the Terran worlds. Fast forward many years, it's been more-or-less explained away with [[ExpandedUniverse tie-in literature]]. Still nothing in the games, but this series has always assumed you [[AllThereInTheManual did the reading first]].
* The Keyblade War happened in the background story of Franchise/KingdomHearts long before the events of the game, and the main goal of the villain is to start a new one.
* ''VideoGame/TheElderScrollsVSkyrim'' has The Second Great War between The Empire and The Aldmeri Dominion, which serves as the basis for the CivilWar of the game.
** The {{Backstory}} for ''VideoGame/TheElderScrollsIIIMorrowind'' provides another example from the Elder Scrolls universe. The "War of the First Council" and "Battle of Red Mountain" thousands of years ago set the stage for the plot of the game. The devout, Daedra-worshipping Chimer and atheistic, scientific Dwemer came into conflict in the land now known as Morrowind. After years of fighting, they were [[EnemyMine forced to team up]] to drive out the invading [[ConflictKiller Nords]]. Their alliance remained under the leadership of Chimeri Lord Indoril Nerevar and Dwemer Dumac Dwarfking, known as the "first council." It was a time of great peace and prosperity for both races. However, the Dwemer DugTooDeep beneath Red Mountain and unearthed the Heart of Lorkhan, the [[GodIsDead creator god.]] Chief Tonal Architect, Lord Kagrenec, crafted tools to tap into the power of the heart, hoping to allow the Dwemer to [[AscendToAHigherPlaneOfExistence transcend mortality]]. The Chimer, seeing this as a blasphemy against the real gods in the Daedra, attempted to stop the Dwemer, reigniting their war. Forces led by Nerevar and Lord Voryn Dagoth infiltrated the Dwemer Red Mountain stronghold. [[TheRashomon Exactly what happened next is up for intense debate]], but the Dwemer disappeared from existence, Nerevar was slain, Dagoth Ur and the Tribunal used the tools on the heart to [[AGodAmI achieve godhood]], and Azura cursed the Chimer with dark skin and red eyes, transforming them into the modern Dunmer.
* ''VideoGame/{{Fallout}}'' - since all the playable characters lives a couple of centuries after the [[TheEndOfTheWorldAsWeKnowIt nuclear war]], you never actually live it, but you see [[CrapsackWorld the effects all around you.]]
** Kinda adverted with ''Fallout 3'' with the "Operation Anchorage" simulation, where you (virtually) fight a small part of the war to reclaim Alaska from the Chinese before the bombs dropped, though notes around the facility record that the simulation has been repeatedly rewritten at the orders of a general, and bears less and less relation to the reality.
* The battle with the quiskerians and the death of Phaeton in ''VideoGame/LegacyOfHeroes''
[[/folder]]

[[folder:Western Animation]]
* {{Franchise/Transformers}}: Has this to varying degrees, the Cartoon itself is a straight example, as the war has restarted on earth and the million year war on Cybertron is only alluded to.
* ''AdventureTime'' has the Mushroom Wars, which caused [[ApocalypseHow the end]] that the series [[AfterTheEnd takes place after.]] Recent season have delved further into into just what happened then, revealing that what seems to be a FantasticNuke was involved, leading to the return of magic and a wave of mutations that resulted in the many oddities of Ooo.
* ''{{SonicSatAM}}'' has a briefly-mentioned "Great War". [[BigBad Robotnik]] had put himself into a position to take over by [[NoodleIncident helping Mobotropolis win it.]]
[[/folder]]

[[folder:Real Life]]
* Various real-life conflicts, such as [[TheAmericanCivilWar The American Civil War]], [[WorldWarOne World War I]], and, for nearly everyone, [[WorldWarII World War II]].
[[/folder]]