->''"First there was the collapse of civilization... anarchy, genocide, starvation... then we got ThePlague."''
-->-- OpeningNarration, ''Film/{{Cyborg}}''

Long ago in the kingdom of [[MagicalLand Troperia]], a great disaster swept through the land. Many lives were lost and, to this day, no one knows what caused the event that has come to be known only as the Cataclysm. Some say that the members of an [[AncientConspiracy ancient society with mysterious, unknown goals were behind it]]. Others say that [[GovernmentConspiracy the powers that govern the people are hiding something]]. No one is completely sure how or why the Cataclysm came to pass, but [[OmnicidalManiac (almost)]] all can agree: the world would be better off if the Cataclysm never came to repeat itself...

... A typical use of the Cataclysm Backstory trope.

Often used in fantasy works, Cataclysm Backstory is a trope that can easily set up the events of a story, or possibly the entire setting itself. It's very common in dystopia works and often used in stories that take place AfterTheEnd. Cataclysm Backstory can be used in many different ways. It can sometimes provide a touch of mystery to any work, only being mentioned every now and then and possibly kept unexplained until much later in the story [[PlotHole (if it's ever explained at all)]]. If done well, the Cataclysm Backstory in question will be deeply tied in with the events of the plot and explained in detail. If done poorly, it will be used as an easy way of filling any given PlotHole (i.e. Where did that HumongousMecha come from? It was revealed during the Cataclysm).

Contrast FirstEpisodeSpoiler. Compare GreatOffscreenWar.


[[folder:Anime and Manga]]
* ''Anime/GuiltyCrown'' has Lost Christmas, a well-done case where [[TheVirus the Apocalypse Virus]] was released. The first two minutes after the opening of episode one are used to explain how Lost Christmas caused Japan to clamor for help from outside governments in order to keep the virus under control, sacrificing their independence in exchange for stability and setting up the events of the main series ten years later. It goes a lot deeper than that, though. [[spoiler: Episode 11 reveals that a small group of people ''intentionally'' released the virus.]]
* ''Literature/DemonCityShinjuku''. Rebi Ra kills his opponent Genichirou and causes an earthquake, devastating the Shinjuku area of Tokyo and leaving it a demon-haunted ruin. Ten years later Genichirou's son must enter Shinjuku and stop Rebi Ra from performing a ritual that will allow demons to conquer the Earth.
* ''Anime/TheBigO''. Forty years earlier an unknown disaster wiped out human civilization. Only those within the main city and its surrounding landscape remain, but none can remember what happened on that day. It's heavily implied that [[spoiler:''nothing'' existed before that point; that everyone is either a robot or a [[TomatoInTheMirror clone]], what few "memories" remain are simulated, and the city itself is an artificial construct. If the whole setting isn't actually InsideAComputerSystem and everyone is a program... But the GainaxEnding was doing its best to out-do EVA anyway]].
* The Hydrus Beta supernova shockwave that very nearly wiped out humanity 200 years ago in ''Anime/StellviaOfTheUniverse''.
* In ''Manga/{{Akira}}'', the Fall of Tokyo, triggered by the awakening of the title character's incredible psionic abilities.
* ''Anime/CowboyBebop'' has the Gate Disaster, which left Earth a ruin that is constantly bombarded by asteroids. Several one-off characters are connected to it, as well as [[spoiler: Faye]].
* ''Anime/NeonGenesisEvangelion'' gives us Second Impact. By the time the story starts, humanity is just starting to return to normal.
* ''Manga/PandoraHearts'' has the Tragedy of Sablier: a hundred years ago, the former capital was thrown into [[EldritchLocation the Abyss]] by [[BadassFamily the Baskervilles]]. In present time, the Baskervilles return and send the main character, [[GuileHero Oz,]] into the Abyss for a crime he knows nothing of, prompting him to investigate their true identity. As it turns out, most of the cast is closely related to the Tragedy. [[spoiler:It has a lot to do with TimeTravel.]] The whole truth is eventually revealed via [[WhamEpisode several chapters]] of [[WholeEpisodeFlashback flashbacks]].
* The [[DetonationMoon Heaven's Fall]] disaster as a result of the GreatOffscreenWar 15 years prior in ''Anime/AldnoahZero'' sets up for the current state of the world.
* The ''Anime/TekkamanBlade II'' OVA has the Prague Black September, a revolt of "Primary Tekkamen" (humans partially transformed by the alien Radam to gain armored bodies but not offensive powers; they were fighting discrimination from "normal" humans) that was put down with the use of nuclear weapons. Only one major character lacks ties to the event, and one character has frequent flashbacks to the burning city. Also, it happened in the wake of an alien invasion that nearly wiped out humanity.
* In ''Webcomic/{{Kubera}}'', all the sura clans suddenly went to war with the gods around the time Leez was born. Entire planets were destroyed and [[HalfHumanHybrid Halfs]] got caught up in [[FisherKing emotional resonance]] and went berserk as a result. Bonus points for the event actually being referred to as the Cataclysm.

* Peter Greenaway's {{Mockumentary}} ''The Falls'' is about how people were changed by the "Violent Unknown Event".

* Literature/TheSevenRealmsSeries gives us The Breaking. At first kept very ambiguous, its eventually explained (in much detail) that many millennia ago, The Demon King kidnapped Princess Hanalea and subsequently performed an act of dark magic that caused a series of natural disasters to sweep the whole of the Seven Realms. Unluckily for him, Hanalea was a BadassPrincess that eventually brought him down. [[spoiler:Or so the people come to believe...]] Anyway, fast forward ten thousand years, and street rat Han Alister gets a hold of the Demon King's amulet.
* The Sixty Minute War in ''Literature/MortalEngines''.
* ''Literature/TheHungerGames:'' We never really find out what killed most of humanity and brought about the founding of Panem (though there seem to be lingering environmental consequences). We gradually learn a bit more about the [[GreatOffscreenWar more recent "Dark Days"]] when the Districts rose in (unsuccessful) rebellion against the Capitol, resulting in the institution of the Hunger Games.
* Of the "no one knows" variety in ''Literature/{{Divergent}}'', something has caused Chicago to isolate itself from the rest of the world, turning the society into the five virtue-based factions in the story.
* The Doom of Valyria in ''Literature/ASongOfIceAndFire.''
* ''Franchise/TheWitcher'' series had the Conjunction of the Spheres, which occurred several centuries prior to the saga and brought hordes of chtonic monsters into the world, where they thrived on a healthy human diet. The eponymous witchers (superhuman monster hunters) were invented to protect the local humanity from these monsters, though they've been so efficient over the centuries that their existence is almost obsolete by the time the books takes place, as there are very few monsters for them left to hunt.
* The nuclear catastrophe in Tatyana Tolstaya's novel ''Kys'', which had set the world into a weird state the inhabitants feel natural.
* ''Literature/TheWheelOfTime'' has the Breaking of the World about 3,000 years before the bulk of the series begins, which finally pushed civilisation from advanced to pseudo-medieval.
* ''Literature/HeraldsOfValdemar'': The [[WorldWreckingWave magical Cataclysm]] that occurred 3,000 years in the past of the main story is alluded to in several places but not explored in detail until the "Mage Wars" trilogy, which establishes the necessary details to seed the plot for the "Mage Storms", which involves the return of said Cataclysm.
* There are several Cataclysms in the background of ''Literature/TheLordOfTheRings'', most notably the sinkings of Beleriand and Númenor, which led to the decline of the Elves and the Dúnedain respectively.
* Creator/VladimirVasilyev's ''The Treasure of the Kapitana'' takes place eight centuries after something called the Catastrophe. Despite the fact that the people of the world know exactly ''when'' it took place (they restarted the [[AlternativeCalendar calendar]] to mark the event), they have no idea what wiped out the Ancients and threw civilization back. By the time of the events of the book, the new Middle Ages have arisen. The ending makes vague references that it was the [[spoiler:lack of magic]] that resulted in the Catastrophe but fails to reveal anything of consequence. For some strange reason, the new civilization refers to places and nations using their ancient names, usually dating back to Greco-Roman times. This can confuse some readers wondering what the hell the Euxine Sea is (it's what the Greeks called the Black Sea, and the Brits continued to use the Greek name until the 18th century).

[[folder:Live-Action TV]]
* ''Series/{{Revolution}}'': The premise of the story is that a worldwide blackout occurred and stays in effect for 15 years. As the first season goes on, more on the backstory is revealed. [[spoiler:The power was shut down by electricity absorbing nanites that were created by Rachel Matheson and Ben Matheson. Randall Flynn, representative of the Department of Defense, was happy to fund their project. From a secret location in Colorado known as the Tower, Randall activated the nanites in Afghanistan in response to his son's death. Unfortunately, the nanites got out of control and spread throughout the world and non just Afghanistan. Aaron Pittman is able to find out that the nanites did not go out of control by accident. It seems that someone deliberately programmed them to spread out of Afghanistan, but there is no way of knowing who could have done that and why.]]
* [[Series/ThatMitchellAndWebbLook DON'T THINK ABOUT THE EVENT!!!]]

[[folder: Mythology and Religion]]
* The [[http://en.wikipedia.org/wiki/Fall_of_Man Fall of Man]] in Abrahamic faith. Also TheGreatFlood.

* "The Withering" in ''Radio/{{Nebulous}}''.

[[folder:Tabletop Games]]
* ''TabletopGame/{{Greyhawk}}'' has the Twin Cataclysms: the Invoked Devastation and the Rain of Colorless Fire.
* The Day of Mourning that played a big part in ending the Last War in ''TabletopGame/{{Eberron}}''. No one knows what caused it or which of the Five Nations was responsible, but we know it wiped Cyre off the map and rendered it an inhospitable wasteland known as the Mournland.
* ''Literature/{{Dragonlance}}'' has the Cataclysm, which went down when the Kingpriest of Istar demanded to be given godlike powers to eradicate evil from the world (more specifically, to genocide the ogre races and relocate the dwarves and kender). The gods were not pleased, and punished him by wiping the city of Istar off the face of Krynn, creating what has since been called the Blood Sea of Istar due to the thick red soil churned up by the sea creating a blood-like appearance; as well as splitting apart the Kingdom of Ergoth, messing life up for several cities (one inland city found itself becoming a coastal city because of a new inland sea, and a port city found itself becoming an inland city surrounded by plains), and outright destroying several more cities including Xak Tsarosk.
* ''TabletopGame/{{Exalted}}'' has two consecutive ones in the form of the Great Contagion (wiped out the majority of all life) and Balorian Crusade (dissolved a significant portion of the world.
** Autochthonia has a relatively small scale version in the destruction of the patropolis Ixut, which kickstarted the [[GreatOffscreenWar Elemental War]].

[[folder:Video Games]]
* The Black Beast rampaging all over the world in ''VideoGame/BlazBlue''.
* ''VideoGame/{{Warcraft}}''[='s=] Sundering is this, although the more recent event that is actually called the Cataclysm is not.
* ''VideoGame/WhiteKnightChronicles'' gives us, well, the Cataclysm. It happened about seventeen years before the start of the story and it's only mentioned a few times in the entire series, but it's the basic explanation for how the [[LostTechnology Yshrenian]] [[HumongousMecha Knights]] [[spoiler:and the heroes as babies]] were revealed. No real explanation is given, but it's heavily implied to be because [[BecauseDestinySaysSo it was simply time for Emperor Madoras to rear his ugly head again, and for him to be defeated]].
* The Collapse, a [[CrypticBackgroundReference oft-mentioned but never-explained]] cataclysm that separates ''VideoGame/TheLongestJourney'' and ''VideoGame/DreamfallTheLongestJourney''.
* Whatever destroyed the Prothean civilization in ''VideoGame/{{Mass Effect|1}}''. [[spoiler:Actually, an invasion by the extragalactic genocidal race of giant sentient machines known as the Reapers. And this is far from the first time they've done this.]]
* Hinted at in ''VideoGame/TheLegendOfZeldaSkywardSword'', and, by extension, the rest of the ''[[Franchise/TheLegendOfZelda Zelda]]'' series to which it is a prequel. The cataclysm in question was invasion by demons, and before it, there was a civilization of sapient robots with technology to put modern Earth to shame. After it, the setting MedievalEuropeanFantasy with a bit of LostTechnology scattered here and there, [[MedievalStasis which then becomes the status quo for thousands of years]].
* ''VideoGame/{{Fallout}}'' takes place in the aftermath of the Great War, a nuclear apocalypse that created the game's ScavengerWorld.
* The defilement of the Golden City by Tevinter Magisters in the ''Franchise/DragonAge'' series, which gave rise to the [[GreatOffscreenWar First Blight]] and placed the future generations into constant danger of a Darkspawn invasion. [[spoiler: At least, so the Chantry would have us believe. ''Some'' calamity instigated the Darkspawn, but the truth has been [[RiddleForTheAges lost to time]].]]
** According to a DLC in the sequel, the Chantry's version is actually partly true, but the Tevinter Magisters who were supposedly the ones who corrupted the Golden City (giving the rise to the Darkspawn) claim that they found the city already Dark.
* This is the case in ''VideoGame/DarkSouls''. The First Flame, the source of all fire and light and disparity in the world is on the verge of dying. This is actually the second time this has happened. The first time happened about 1,000 years before the main events of the game, and caused the loss of the two most proactive Lords, Gwyn and Izalith, the complete downfall of the city of Izalith, unleashed demons onto the world and set in motion the events that caused the gods to abandon Anor Londo.
* Many of the plotlines in the ''VideoGame/AceCombat'' series can be traced back to the Ulysses 1994XF04 asteroid impact in 1999. Most of the gigantic superweapons involved in later Strangereal wars (Usean Stonehenge, Erusian Megalith, Estovakian Chandelier) were originally built to protect their respective nations from Ulysses' fragments, and at least two conflicts ([[VideoGame/AceCombat04ShatteredSkies Usean]] and [[VideoGame/AceCombat6FiresOfLiberation Anean Continental Wars]]) were immediate consequences of the devastation caused by the debris that did get through. Additionally, the Osean-Yuktobanian space station ''Arkbird'' from ''VideoGame/{{Ace Combat 5|TheUnsungWar}}'' was originally commissioned to clean up the Ulysses debris still floating in orbit.
* The Silence serves as this in ''VideoGame/HeroesOfMightAndMagic I''-''III'' and ''VideoGame/MightAndMagic VI''-''VIII''. In the ''Heroes'' series, it is a CrypticBackgroundReference to the point that it isn't even explicitly indicated to be this trope, while the ''Might & Magic'' games goes into more detail, revealing early on ''what'' the Silence was (the colonial masters of the planet, the Ancients, withdrew for unknown reasons, and the loss of inter-planetary travel lead to a collapse of high-technological civilization), and in the end-games ''why'' it happened ([[spoiler:the [[PlanetLooters Kreegan]] attack on the Ancient civilization damaged Ancient infrastructure across the local galactic arm, leading to a loss of contact with many of their colonies. The Ancients would have rebuilt the links, except they're still busy fighting the Kreegan]]).
* The [[spoiler:Fall of Cocoon]] that took place in the end of ''VideoGame/FinalFantasyXIII'' shapes the world to a great extent in ''VideoGame/FinalFantasyXIII2''.
* The Keyblade War from ''Franchise/KingdomHearts''. Apart from anything else, the numerous tiny and largely cut off from one another worlds the series takes place on used to all be one planet prior to the War.
* The Elf Wars, set between the ''VideoGame/MegaManX'' and ''VideoGame/MegaManZero'' series. The conflict lasts only four years, but the casualties that are tallied reach up to approximately 60% humans and 90% Reploids.
* The Crusades in ''VideoGame/GuiltyGear'', a bloody altercation wherein the Gears, led by the [[MonsterLord Commander Gear]] Justice, TurnedAgainstTheirMasters and set forth to KillAllHumans. Beginning in the year 2074 with Justice's revolt, the war lasted over a century, only finally ending in 2175 when [[TheKnightsTemplar the Holy Order]] [[SealedEvilInACan sealed away Justice in an extradimensional prison]]. It's unknown how widespread the damage was, but America--the country responsible for starting the Gear Project--[[FallenStatesOfAmerica has fallen into ruin and is now simply known as A Country]] (Sol's stage in the original game [[SceneryGorn is that of a]] {{ruin|sOfTheModernAge}}ed New York City, complete with [[MonumentalDamage the severed head of the Statue of Liberty]]), London was once at risk of being razed by [[{{Kaiju}} a Megadeth-class Gear called Hydra]], and, in one of the very first acts of war, ''[[TheTokyoFireball the entire country of Japan was obliterated]]'', with the surviving Japanese being relegated to colonies and classified as "national treasures." What's worse, [[ForWantOfANail there exists]] [[BadFuture a timeline]] [[ForWantOfANail where]] [[spoiler:I-No [[TimeTravel goes back in time]] and [[ForTheEvulz manipulates events at a whim]], leading to the death of Ky Kiske at the Battle of Rome in 2173. This is treated as a ''worldwide'' DespairEventHorizon and causes the Crusades to extend at least into 2183, with Justice's daughter Dizzy taking charge of the Gears in her fallen mother's place]]. It's implied the fallout here is much, ''much'' worse.
* Permeates ''VideoGame/SkiesOfArcadia''. About a thousand years ago, the world's six Moons suddenly dropped a bunch of meteors on the planet below, pummeling the ancient civilizations into the stone age in an event called the Rains of Destruction. By the start of the game, humanity has only just about recovered to the equivalent of Age of Discovery technology. [[spoiler:And there are factions who are trying to make the Rains fall again...]]
* In the expansion of ''VideoGame/SidMeiersAlphaCentauri'', it's revealed that the planet called Alpha Centauri/Chiron is actually an ancient experiment on planetary-scale artificial sentience using genetically-engineered ecosystems called "Manifold Six", created by a race of {{Precursors}}. 100 million years ago, another Manifold, Tau Ceti, gained planet-wide sentience resulting in a massive psionic disruption which annihilated three systems and broke the back of the Progenitor civilization. The surviving aliens have split into two factions, the Manifold Caretakers who are determined to locate and protect the remaining Manifolds so they remain in their dormant state, and the Manifold Usurpers who apparently didn't learn their lesson and are trying to find another Manifold and activate it so they can achieve godhood.

[[folder:Web Original]]
* ''Roleplay/OpenBlue'' has two: first was the fall of the [[{{Precursors}} Iormunean Imperium]] 1200 years ago, which is directly responsible for the existence of at least one major power in the setting, and indirectly responsible for another. The second was the more recent Disaster of Nations 3 months ago, which is responsible for the weakening of the world superpowers, and the return of the Pirate Lords to power.

[[folder:Western Animation]]
* The Land of Ooo in ''WesternAnimation/AdventureTime'' is implied to be our world AfterTheEnd, and there is mention of a [[UsefulNotes/NuclearWeapons "Great Mushroom War."]] This explains why there are electronics in an otherwise MedievalStasis fantasy world, and the presence of RuinsOfTheModernAge. Season 5 finally just flat out confirms it and hints at what caused the cataclysm. [[spoiler: Apparently it involved a nuclear war and the return of magic to the world.]]
* ''WesternAnimation/GeneratorRex'': A massive FreakLabAccident infests the entire world with [[{{Nanomachines}} nanites]], which cause extreme mutation on much of the population. Most of the major characters are implied to be somehow connected to the event.