->''"1865 - [[TropeNamer Alien bats from outer space]] bring the fruits of their technology to their brothers, because they have heard Music/ElvisPresley on the radio, and think that the south should indeed be free. It ranks slightly higher than a '63 CSA victory. [[TakeThat Indeed, I think I will call it]] "[[TheGunsOfTheSouth Bats of the South]]", [[TrilogyCreep and make it into a four book trilogy]]."''
-->-- '''Alison Brooks''', discussing the probability of various AlternateHistory [[ClicheStorm Confederate victories]] in UsefulNotes/TheAmericanCivilWar on [=soc.history.what-if=]

An AlternateHistory trope dealing with the divergence of a timeline. The phrase is widely used on Alternate History websites. If the point of divergence is an extraordinary or supernatural phenomenon, Alien Space Bats are responsible. If history changed due to historical happenstance it was just ForWantOfANail.

Alien Space Bats is in a sense the opposite of DeusExMachina: where DeusExMachina is the introduction of an implausible element outside of the context of the narrative to ''resolve'' a plot conflict, Alien Space Bats are an implausible element outside the context of the narrative introduced in order to ''set up'' the main plot conflict or setting of the story.

The phrase was originally coined by the late Alison Brooks as a sarcastic comment on ridiculous Alternate History timelines with no realistic chance of happening without some sort of DeusExMachina as implausibly contrived as bringing in a bunch of SufficientlyAdvancedAlien bats. It was only later that it came to mean "explicitly magical or science-fiction what-ifs."

The trope may also apply when the point of divergence isn't actually supernatural, but so wildly implausible that it might as well be that AWizardDidIt.

Note that TropesAreNotBad: this can and does lead to some excellent yarns, especially if SchizoTech is involved. Even if the event setting up the plot is fantastic or wildly improbable, [[TheyPlottedAPerfectlyGoodWaste that doesn't mean that the character's reactions to it have to be equally unrealistic]].

A frequent mechanism by which Alien Space Bats intervene in human history is MassTeleportation. When on a small scale, their intervention may leave people TrappedInThePast. See also NeverWasThisUniverse.

Not to be confused with GoddamnBats, or the Franchise/{{Batman}} from ''SpeedingBullets,'' who actually ''is'' an alien. Only vaguely related to the movie [[{{Film/Lifeforce}} Lifeforce]], which is not AH, but has ''literal'' alien bats.

[[http://en.wikipedia.org/wiki/Alien_space_bats Now a verifiable wiki article]]! That cites this very page on ThisVeryWiki!

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!!Examples:

[[foldercontrol]]

[[folder: Anime and Manga ]]

* ''{{Zipang}}'' diverges from history in the wake of the Battle of Midway when a modern Japanese Aegis destroyer is sent back to 1942 by a NegativeSpaceWedgie.
%% Code Geass is not this trope. It's Never Was This Universe--there are far too many points where the timeline diverges from ours. Commented in in order to keep people from trying to re-add Code Geass as an example here, and Code Geass is already an example on the Never Was This Universe trope.
* The world of ''Manga/FullmetalAlchemist'' (or at least that of [[Anime/FullmetalAlchemist the 2003 anime adaptation]]) diverged from the normal world when alchemy was discovered.

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[[folder: Comic Books ]]

* ''Comicbook/{{Watchmen}}'': The exact point of divergence seems to be the presence of "costumed heroes", which isn't ''too'' fantastic([[BadassNormal none of them have any superpowers]]), but most of the really major differences can be attributed to [[PhysicalGod Dr. Manhattan]], whose appearance marks the point where the course of global politics and history dramatically shift, like the US winning the UsefulNotes/VietnamWar, or the Soviet invasion of Afghanistan put on hold for awhile.
* ''{{Marvel 1602}}'' has everything fairly normal up until the future MarvelUniverse suddenly imposes itself on the past.
* One alternative world ComicBook/TheAuthority fought diverged when blue-skinned aliens arrived in Italy during the Renaissance.
* In the MarvelUniverse, [[ComicBook/BlackPanther Wakanda]] is one such example. Thanks to a meteor of {{Unobtainium}}, the Wakandan people developed advanced technology early, and thus were never colonized by European nations.
* The crashed alien spaceship in {{Comicbook/Miracleman}}.
* ''ComicBook/{{Uber}}'': Shortly before the Fall of Berlin, the Nazis develop superpeople using alien technology. Subsequent developments, in a deconstruction of StupidJetpackHitler, are carefully thought through and extremely depressing.
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[[folder: Fanfiction ]]

* ''FanFic/AScotsmanInEgypt,'' an epic TotalWar AfterActionReport, starts off with two drunk Scottish princes invading Egypt... and ''winning.'' And they (and their successors) [[TakeOverTheWorld don't stop there.]]

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[[folder: Film ]]
* ''TheFinalCountdown'' and a few imitators also have some sort of NegativeSpaceWedgie toss an individual, a country, or a military force back or forward in time so they can change history.
** ''TheFinalCountdown'' was a StableTimeLoop. Imitators, however, may not include this aspect.
* Possibly referenced in ''WesternAnimation/JusticeLeagueCrisisOnTwoEarths''; when Superwoman is trying to decide which alternate Earth to send Batman to, she glosses over one where humanity has "mutated into hideous winged creatures of the night".
[[/folder]]


[[folder: Literature ]]

* The ''Literature/SixteenThirtyTwo'' series has a small modern American town physically relocated to 17th-century Germany by some process that the author discusses no further than to vaguely say that advanced physics could probably explain it. It does give a tiny bit of exposition about the Space Bats in question (an alien species that thinks of creating temporal anomalies as being True Art), and notes that eventually, they get their just desserts at our descendants' hands for the general hazard their art poses, but that's all in the prologue, after which they never appear again.
* John Birmingham's ''Literature/AxisOfTime'' trilogy, inspired by ''TheFinalCountdown'' (see above), depicts a military task force that gets sent [[TimeTravel back in time]] from 2021 to 1942 as a result of a failed experiment on one of the ships in the task force.
** ''Without Warning'' and its sequel ''After America'' also by John Birmingham, set in 2003 and after, features a wave of unknown energy that causes the population of most of North America to be suddenly disintegrated. Other, non-primate animals are either unaffected or destroyed on a seemingly random basis.
* In HarryTurtledove's ''TheGunsOfTheSouth'', the Confederate States win the UsefulNotes/TheAmericanCivilWar because time-traveling South Africans give them AK-47s.
** ''Ravage'' uses an identical premise, but falls under the category of future rather than AlternateHistory, as it takes place in the 21st century and was written in 1943.
** The (nowadays less-known) likely progenitor of the "CSA victory" variation of AlternateHistory, ''Literature/BringTheJubilee'' by Ward Moore, [[{{PlayingWithTropes}} utilizes the trope with a twist.]] The basic premise is a classic example: history is changed by a time traveller affecting [[{{ForWantOfANail}} one small event]] (accidentally, in this case). The twist is that we're shown the AlternateReality throughout the novel, while the actual time travel experiment with its consequences occurs near the end - the reason being that [[spoiler: in-universe, the historical reality ''was'' a Confederate victory (for wholly mundane and plausible reasons) and the AlternateReality of a dominant CSA is the actual reality in the novel. The result of the time traveller's actions is the emergence of an alternate timeline in which the USA won - i.e., our real world ''is'' the alternate reality in the novel's universe.]]
* The ''Literature/BelisariusSeries'' is a good example; its divergence is the result of a TerminatorTwosome of warring [=AIs=] [-FROM THE FUTURE-]. Link was sent by a group of MasterRace-type purists to prevent a future full of what they see as TranshumanTreachery, while Aide was sent by kind, gentle TranshumanAliens (of the SpaceWhale persuasion) Link is trying to RetGone.
* The major point of divergence in the ''WildCards'' franchise is the outbreak of the eponymous virus on Earth, which bestows superpowers on its victims (that is, if you can avoid the [[SuperpowerRussianRoulette horrible death part]]).
* In an intentional {{homage}} to this trope, Creator/KenMacLeod's ''Learning the World'' is set on a planet inhabited by actual Alien Space Bats -- to whom humans are the mysterious alien visitors who change the course of history.
* Creator/KimNewman's ''Literature/AnnoDracula'' series and Creator/NeilGaiman's ''AStudyInEmerald'' have respectively {{Dracula}} and Creator/HPLovecraft's [[EldritchAbomination Old Ones]] as rulers of TheBritishEmpire instead of Queen Victoria. In Newman's, Dracula does this with Victoria's own approval, as her regent.
* SMStirling is noted for this trope, probably because he was a regular reader of the newsgroup where the term was coined:
** ''Literature/TheDraka'' has the initial divergence of American and French royalists being sent to the fictional colony of Drakia. It then has a number of others, such as the existence of an incredibly complete cache of classical literature in Western Africa, and the spontaneous appearance of several technological advances in a culture with little incentive to have them. For example, they send steam-powered warcars to help the Confederacy, and have enough dirigibles to launch an air raid that kills 50,000 people against Russia in the 1880s. They also have atomic bombs by 1944, but so does the United States.
** ''IslandInTheSeaOfTime'' starts with the Event: Alien Space Bats sending Nantucket (and a big ellipse of ocean surrounding the island) [[TimeTravel back in time]] to the Bronze Age.
** The ''{{Emberverse}}'' novels: in the 1998 from which Nantucket was taken, the same Alien Space Bats cause all industrial-level technology to become useless. {{Lampshade}}d as some of the characters explicitly use the term "Alien Space Bats" as a label for whatever unknown force caused most human technology to suddenly stop working.
** ''The Sword of the Lady'', these particular Bats are revealed to be [[spoiler: the ''Mind'', essentially the Jungian Universal Subconscious having an argument with itself]].
** ''TheLordsOfCreation'' series is set in an alternate history where Mars and Venus are habitable (having been made so centuries ago by the eponymous advanced alien race, for reasons not yet revealed).
* HarryTurtledove's ''Literature/WorldWar[=/=]Colonisation'' books - the point of divergence is aliens invading during UsefulNotes/WorldWarII.
* In the RogerZelazny book ''Roadmarks'', the [[TimeTravel time-traveling]] main character keeps attempting this to fix Thermopylae (in the story the Greeks lost) but the TimePolice keep catching him.
* Elizabeth Bear's '' [[Literature/NewAmsterdamBooks New Amsterdam]]'' has alien space bats in the form of magic warcraft used by Native Americans, preventing Europeans from settling the Americas except spottily along the coasts.
* ''Thor Meets Captain America'' by Creator/DavidBrin has Nazi Germany essentially winning World War II because they were able to summon the Norse gods to fight on their side. [[spoiler:They ultimately lose it all when Loki - whose titles include "The Ever-Contrary" - betrays them.]] AlienSpaceBats was used to make a point here: this was the ''most plausible scenario'' the author could think of that would have the Nazis winning.
* Steven White's ''Saint Antony's Fire'' starts off with Ponce de Leon discovering the wreck of an interdimensional UFO, quickly followed by the resurrected aliens allowing the Spanish Armada to successfully invade England.
* Naomi Novik's ''Literature/{{Temeraire}}'' series is set in the Napoleonic Wars in a universe where ''dragons'' exist and are widely used by humans, especially militaries. The AlternateHistory elements are [[InSpiteOfANail not immediately apparent]], but there are numerous key differences; the Incans, for instance, are a major world power because of their dragons, and the Chinese, far from being in decline and getting bullied by Western powers, are one of the major players in the war as both sides try to enlist their aid, or at the very least keep them from joining the other side.
* Taylor Anderson's ''Literature/{{Destroyermen}}'' series has the Squall, a bizarre, recurring storm that has repeatedly transferred ships from our Earth to an alternate timeline where the K-T extinction event did not occur.
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[[folder: Live Action TV ]]

* A few ''{{Sliders}}'' episodes fell into this, with worlds where physical laws permitted magic and wizardry and dragons, whereas other worlds were ForWantOfANail. Still other worlds the Sliders visited combined these aspects.
** Interestingly, only one world had an event that fits the "alien" bit. According to the show, all those alien conspiracies on other worlds are actually true. The only difference on this world is that the government went public with FirstContact and established open trade with the Reticulans, resulting in many technological advances (including a virtual panacea, anti-gravity, and a manned mission to Mars). Disappointingly, the characters themselves don't actually get to meet any aliens. The best they get is a human who looks part-Reticulan thanks to a side effect of the panacea drug (his blood is also green).

[[/folder]]

[[folder: Other Internet ]]

* Alison Brooks introduced the alien bats to [=soc.history.what-if=] in her AlternateHistory spoof ''[[http://www.changingthetimes.net/samples/brooks/original_alien_space_bats.htm Irony And Steal]]''. Here, the bats descend on Manchester, England at the start of the Napoleonic Wars, having learned how to [[AliensSpeakingEnglish speak English]] from [[AliensStealCable listening to future radio broadcasts]], and supply tanks to Britain with which it can defeat France at El Alamein. Silliness ensues, including the Russian Czar marrying a bat, [[ZeppelinsFromAnotherWorld dirigible arms races]], [[RichardNixonTheUsedCarSalesman Lenin becoming a baseball player]], and alien mutant ninja turtles replacing the population of Australia.
* On the Spacebattles forums, an entire section of the site is dedicated to what they call "Random Omnipotent Beings," or "[=ROBs=]" doing precisely this, starting off many role-play threads.

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[[folder: Tabletop Games ]]

* The {{GURPS}} "Infinite Worlds" campaign has two major opposed alternate-reality-jumping factions (Homeline, our world circa 2027 if [[AppliedPhlebotinum paratemporal technology]] had been invented in 1994, and Centrum, a recovered post-apocalyptic OneWorldOrder of {{Straw Vulcan}}s with similar tech) often act as AlienSpaceBats in other timelines to further their own interests (which right now is mostly screwing up the rival faction). The players are probably going to work for one or the other.
* ''TabletopGame/{{Shadowrun}}'' has two small ones and one big one;
** In 1999, the Supreme Court grants certain major corporations the right to form ''private armies'' as "ex post facto" justification for ending a vicious food riot with a massacre instead of permitting the rioters to accidentally start an outbreak by eating hazardous medical waste. It's implied that the "[[http://shadowrun.wikia.com/wiki/Seretech_Decision Seretech Decision]]" was planned in advance from riot to lawsuit, because it's kind of stupid to transport hazardous medical waste through Manhattan during a food riot...
** Especially because the same year, the NRC was forced to give another corporation its own ''nuclear power plant'' rather than be accused of graft. And the corporation was able to spin an ecoterrorist attack on the plant into nationhood(the "[[http://shadowrun.wikia.com/wiki/Shiawase_Decision Shiawase Decision]]") by saying they'd have been able to protect the place better with mercenaries instead of local cops. And an attempt by the ecoterrorist group to clear their name is interrupted by a bombing believed to be the first shadowrun.
** The ''real'' ASB is when TheMagicComesBack in 2011...
* ''TabletopGame/{{Deadlands}}: The Weird West'' starts with a vindictive Native American shaman unleashing SealedEvilInACan, which leads to all sorts of weirdness, like the Battle of Gettsyburg being interrupted by zombies, and a huge earthquake splitting southwest California into a series of canyons lined with a new mineral called "ghost rock", which is basically coal that burns more efficiently but also makes creepy noises. And that's just for starters...

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[[folder: Theme Parks ]]

* The roadside attraction "[[http://io9.com/5084491/the-alternate-history-theme-park-where-dinosaurs-fought-in-the-civil-war Professor Cline's Dinosaur Kingdom]]" features an alternate version of the UsefulNotes/TheAmericanCivilWar where [[NinjaPirateZombieRobot the Union army tried to arm itself with dinosaurs]]. [[EpicFail It didn't turn out so well.]]

[[/folder]]

[[folder: Video Games ]]

* In Failbetter Games' browser game ''VideoGame/{{Fallen London}}'', Victorian-era London was literally stolen by bats.
* The ''VideoGame/{{Resistance}}'' series is based entirely around this trope, where the alien Chimeras arrive in the Tunguska event of 1908. In 1921, Russia initiated a communications blackout with the rest of the world, and built a wall against its European border called the "Red Curtain". In December 1949, the Chimeran forces invade mainland Europe. The first game starts with their invasion of England in 1951.
* The backstory for ''DawnOfVictory'', a mod-in-development for ''SinsOfASolarEmpire'', is inspired by the ''Literature/WorldWar'' series in that it involves aliens invading during [[UsefulNotes/WorldWarTwo WW2]] and proceeding to kick everybody's ass, except for a few isolated victories. Then nukes are developed and used, pushing the Scinfaxi to the Southern Hemisphere. History then proceeds similar to ours in the Western world, except there are three superpowers: [=USSR=], Germany, and the Democratic Federation.
* In ''Robo {{Aleste}}'', the arrival of a mysterious foreign derelict ship introduces to Sengoku period Japan firearms, airships and HumongousMecha.
* ParadoxInteractive is normally known for creating highly-detailed, well-researched historical RealTimeStrategy games that try to err on the side of plausibility in modeling the setting. This is why several fans were, to put it mildly, taken by surprise when they launched the ''Sunset Invasion'' minor DLC for ''VideoGame/CrusaderKings II'', which introduces a massive invasion of Western Europe by [[{{Irony}} a technologically-advanced, disease-spreading]] [[{{Mayincatec}} Aztec Empire]].
* As of 2010, ''VideoGame/GuiltyGear'''s discovery of a physics-defying energy source that kicks off [[GeneticEngineeringIsTheNewNuke a genetically engineered monster apocalypse]] and turns the whole world into the cover of every metal album ever has officially become this.
[[/folder]]

[[folder:Western Animation]]
* In WesternAnimation/{{Futurama}}, a jerk from the XX century who was living in the XXXI century and who made time travel, messed with a signal during the American Revolutionary War, that led to the British victory. When they return to the XXXI century, the US is now British, it has always been British... at least, until they made another trip to SetRightWhatOnceWentWrong.
[[/folder]]

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