[[quoteright:323:[[Franchise/{{Tintin}} http://static.tvtropes.org/pmwiki/pub/images/pretext_for_war_4.jpg]]]]

->''He messed with the H.R.E. - Casus Belli.''\\
''Shattered Stability - Casus Belli.''\\
''Prussia, Denmark, France - This is a call to arms!''\\
''England stood no chance - This is a call to arms!''\\
''But we couldn't be happier, now that he attacked,'' \\
''We have '''Casus Belli'''!''[[note]]''Casus Belli!'' '''Casus Belli!''' ''Casus Belli!'' '''Casus Belli!''' ''Casus belli!'' '''Casus Belli!'''[[/note]]
-->-- "[[http://www.youtube.com/watch?v=nUZvwxucXbw Casus Belli]]", ''VideoGame/EuropaUniversalis IV: TheMusical''

The leaders of Viridia and Tyria want to go to war. Not for a {{silly reason|ForWar}}, but due to anything from good old fashioned jingoism, greed, political/economic/religious differences, or a simple historical grudge. However, they can't just out and out declare war, [[SarcasmMode that would be uncivilized!]] And more importantly, it would make them look bad to the international community, which isn't good politics. So instead they will wait for or manufacture a Pretext for War out of whatever should come their way.

Did a Tyrian pig farmer lose a pig when it wandered into Viridia? ThisMeansWar Maybe a Viridian girl disappeared near the Tyrian border? Tyrian slavers must want to [[MarsNeedsWomen capture Viridian women]] since theirs are so ugly! A favorite is for StarCrossedLovers from both sides (preferably royalty) to elope, causing both sides to assume the other kidnapped their heir.

One interesting and {{iron|y}}ic variant is when hardline elements from both sides will collaborate to stage a high profile assassination or other incident to kickstart a war, proving [[NotSoDifferent just how well they work together to achieve their goals despite hating each other's guts]]. This one is especially common when one or both nations have a ReasonableAuthorityFigure as a head of state, since it can force their hand to war, or if they're the assassination target, get them out of the picture ''and'' make them an unwitting martyr. FalseFlagOperation is one of the classical moves too, and almost a Twentieth Century theme song.

Point is, an incident any two sane heads of state would quietly defuse is treated as a RantInducingSlight in order to start the war. In these cases, heroes typically have to uncover the plot in order to PreventTheWar.

A technical term for this is the Latin term ''Casus Belli'', or case for war.

Since [[http://en.wikipedia.org/wiki/War_of_aggression wars of aggression]] have technically been banned, you'll find that these are a lot more common today than they were previously, since both sides are at pains to show that the other side started it. As a result, the history of many a 20th-century war reads like a really, really dark [[IdiotPlot Idiot]] FawltyTowersPlot. Mind you, "civilized" countries have more or less always deemed it improper to declare war on your neighbors "because we want your stuff" or "because we feel like it;"[[note]]With the exception of Sparta, which freely admitted that it would go to war "[[BloodKnight because we have nobody else to fight right now]]."[[/note]] even an aggressive war would have to have some kind of triggering incursion, insult, or violation behind it. (Look up how each of the three UsefulNotes/PunicWars got started--the pretexts are hilariously flimsy.)

See also WarForFunAndProfit.


[[folder:Anime and Manga]]
* ''LightNovel/CrestOfTheStars'': The United Mankind attacks an Abh ship through a previously unknown hyperspace lane, then declares that they were attacked first and destroyed the ship in self-defense. They use this incident to begin stirring up their allies and begin to build an excuse to go to war with the Abh. The Abh Empress doesn't believe for an instant that the Abh ship is to blame, realizes what the United Mankind is up to, and decides to just cut to the chase and declare war ''immediately'', which catches the United Mankind and their allies off-guard.
* The plot of ''Anime/AldnoahZero'' is kicked off when Princess Asseylum Vers Allusia, the granddaughter of the emperor of Mars, is assassinated in a terrorist attack on Earth during her [[{{Irony}} diplomatic mission]]. The Orbital Knights, the Martian warrior nobility, react immediately with a [[EarthIsABattlefield full-scale invasion of Earth]]. Unbeknownst to the majority of the knights, [[spoiler:the assassination was a FalseFlagAttack perpetrated by a faction of their own government in order to force the conquest of Earth.]]
* A heroic example occurs in ''Anime/YuGiOhArcV'', with [[spoiler:LID]] (Group A) taking advantage of the team from [[spoiler:Duel Academy]] (Group B) going to [[spoiler: Paradise City]] (part of A's territory) on a mission to kidnap two LivingMacGuffin characters. Group A gets footage of B's soldiers using hyper-advanced MagiTech weapons to [[spoiler: seal the souls of]] ([[GettingCrapPastTheRadar metaphor]] [[NeverSayDie for murder]]) bystanders that get caught in the crossfire. The propaganda created from the footage convinces the people of A's home that B is invading, and that they must militarize and fight back. The reason why it's a heroic example is because B already has invaded a different [[spoiler:dimension]] and committed genocide upon it's inhabitants; [[FramingTheGuiltyParty it just hasn't moved onto A's home]] ''[[FramingTheGuiltyParty yet]]'', and the people running A want to ensure that their home is capable of defending itself when the need arises.
* The finale of ''Anime/StarshipOperators'', [[spoiler: the Earth Alliance invades the Henrietta Sector on the pretext of defending the Kiba government-in-exile onboard the ''Amaterasu'' from the Kingdom. However the ''Amaterasu'' crew decide they'd rather not be used like that.]]

[[folder:Comic Books]]
* ''Recap/TintinTheBrokenEar'': A CorruptCorporateExecutive encourages Tintin (then working as the aide to a BananaRepublic's dictator) to declare war on a neighbouring country. Tintin point-blank refuses, so the executive frames him and he's forced to flee the country in a staff car. The car is fired upon by the [[BorderCrossing border guards]] and the incident is then used as an excuse for war.
** Before that, in ''Recap/TintinTheBlueLotus'', there was a thinly disguised replay of the Mukden Incident used as a pretext for additional Japanese intervention in China.

[[folder:Fan Works]]
* ''Fanfic/WhatAboutWitchQueen'':
** The final reason for Arendelle and Weselton to go to war is scout shooting incident, which is a result of tensions building up to the point that two armies are less than a mile from each other. Schemers on both sides set the entire situation up (sending armies, choosing GeneralRipper to be one of the commanders) so it would end that way.
** Hans' plan to keep Westerguard is to start war between Isles and Arendelle by killing Anna and making it look as if it's Islanders' fault.
* At one point in ''Fanfic/EarthsAlienHistory'', the [[TheAlliance Terran Treaty Organization]] colonizes the Rama star cluster, which the [[Manga/OutlawStar Invincible Ctarl-Ctarl Empire]] claims to have already put a stake in (despite never colonizing or occupying). To try and rectify this, Ctarl-Ctarl [[AssInAmbassador ambassador]] Aisha Clanclan conspires with a high-ranked friend in the military to place a fleet on a "training exercise" on the border, in the hopes that they'll be fired upon by [=TeTO=], enabling them to start a war that will result in the Ctarl-Ctarl taking the cluster for themselves. [[spoiler: Except the resulting border skirmish never escalates into a full-scale war, and [=TeTO=] puts more effort into it, so the Ctarl-Ctarl get their asses kicked.]]

* Creator/TheMarxBrothers' ''Film/DuckSoup''. Essentially just bankruptcy and personal slights.
** Some of which were ''hypothetical'' slights that didn't actually happen, at that.
* The plot behind ''Film/ThePrincessBride''.
* ''Film/StarTrekVITheUndiscoveredCountry'' featured [[spoiler:a combined conspiracy by both Starfleet officers and Klingon military leaders]] to try to veer both nations onto the path to war by [[spoiler:having each side's ReasonableAuthorityFigure assassinated by agents from the other side]]. Given how the Federation was definitely in the stronger economic and military position at the time, many fans have since hypothesized that the respective [[spoiler:Klingons]] were goaded into "dying on their feet rather than living on their knees" by [[RetCon Section 31 machinations]].
** The [[Franchise/StarTrekExpandedUniverse novel]] "Sarek" indicates that the the actual masterminds behind this plot were [[spoiler:the Romulans]], who in the movie had seemed to just be bit players.
** In ''Film/StarTrekIntoDarkness'', Admiral Marcus sent Kirk and the Enterprise into Klingon space to take down John Harrison, then sabotaged the Enterprise's warp engines so they would be easy prey for the Klingons, using the destruction of the Enterprise as a pretext to start a war with the Klingon Empire.
* ''Franchise/StarWars'' has many thanks to the machinations of [[EvilChancellor Chancellor]] [[MagnificentBastard Palpatine]]. In ''Film/ThePhantomMenace'', he directs the [[MegaCorp Trade Federation]] to invade [[PerfectPacifistPeople Naboo]] over a trivial dispute, and in ''Film/AttackOfTheClones'' he deploys the clone army secretly created by his apprentice Count Dooku to Geonosis, sparking the Clone Wars.
* When Guy de Lusignan becomes King of Jerusalem in ''Film/KingdomOfHeaven'', he releases Reynald in order for him to do something to start a war with Saladin. In an earlier scene Saladin's adviser had remarked that Guy becoming king meant Saladin didn't have to find one himself since the man was stupid enough to start a war he couldn't win.
* In ''Film/TheManWhoKnewTooLittle'', members of the British and Russian intelligence services are collaborating together for a bombing that would take out the top table of a British/Russian peace conference. The British spymaster is seen longing for the new funding, equipment, and poisons that renewed tensions would bring. When the hero unwittingly starts getting in the way, the Russian spymaster complains, "If we cannot trust each other, how can we bring back Cold War together?"
* In the political satire ''Wrong Is Right'' (1982), two suitcase nukes acquired by a Middle Eastern dictator are found on top of the World Trade Center. After being successfully disarmed, they're used to justify invading that country and seizing its oil. The last thing we see of the dictator as he's being bombed is him complaining that the whole thing was a set-up, as he still has the nukes in his possession. The movie became HarsherInHindsight after the events of 9/11.


* ''Literature/{{Discworld}}'':
** ''{{Discworld/Jingo}}'' is built around one - unsurprisingly, given the name. The excuse for war is a worthless island that's risen from the bottom of the sea after a volcanic event. A strategically vitally located island with plenty of mysterious ruins on it, admittedly, but still, fairly worthless compared to what war would mean.
** As one character pointed out, the island being strategically located only mattered if there was a war, and the only reason they were fighting was ''because of'' the damn island. A more politically acceptable excuse to go to war and seize the island (the attempted assassination of a diplomat) had to be manufactured as a result. Fortunately, Sam Vimes wasn't fooled for a minute and set out to put a stop to it before things got out of hand. [[spoiler:Carrot ended up [[RefugeInAudacity arresting two entire armies for, among other things, Conspiracy to Commit a Breach of the Peace]] and buying enough time for Vetinari to swing a large number of trade concessions in return for ceding the island to the other side... about half an hour before it sinks again.]]
** In ''Discworld/SmallGods'', Vorbis [[spoiler: arranges for one of his own church's missionaries to be murdered on his way back from Ephebe, then blames the Ephebians for killing the man and "counterattacks" with an army he'd sent out to cross the desert before the missionary had even visited their city.]]
** In ''Discworld/InterestingTimes'', Lord Hong is giving extensive support to highly ineffective "revolutionaries" to create a pretext for him to launch a potent counter-revolution. As his long-term goal is to TakeOverTheWorld, he arranges for them to have a figurehead from outside TheEmpire (Rincewind), giving him an excuse to declare war on Ankh-Morpork in the future.
* The manufacture of such a pretext is a major plot point in both the film and book versions of ''Literature/ThePrincessBride''.
* ''LightNovel/CrestOfTheStars'' has a complex one. First is the destruction of the ''Gosroth'' with United Mankind insisting on setting up a joint investigation committee, with the suggestion that tensions are running high after the Abh annex the Hyde System. Ultimately subverted in that it is revealed that UM has been planning the whole thing for decades and on the Abh side Empress Ramaj sees right through it and refuses to play their games. She basically says "If you want a war then I will give you a war."
* Mocked in the ''Series/StarTrekTheNextGeneration'' novel ''I, Q''. The Q Continuum has a mortal enemy, the M Continuum. The Ms decided they wanted to go to war with the Qs. Why? Because there is something about them that pisses them off (their exact words). The Q Continuum requested a more eloquent reason. So one of the Ms insulted the mother of one of the Qs. This horrific affront (despite the fact that this Q, like all other Qs, didn't ''have'' a mother) could only be answered by a full scale war.
** Eh, the YourMom taunt can infuriate many immortal, parentless beings. [[Webcomic/CaptainSNES Amon fell for it]].
* In the third ''Literature/DresdenFiles'' book, ''Literature/GravePeril'', this turns out to be the cause of most of the problems of the books: [[spoiler: the Red Court was ready to launch a war against the White Council, and just needed a good excuse to do so, so they manipulate Harry into breaking SacredHospitality.]] Harry sees that he's being maneuvered into the trap and knows what the consequences will be, but since the alternatives would be the death of him and several innocents, along with the unmaking of a Holy Sword, he does it anyway.
** Only part of [[spoiler:the Court]] wanted to go to war. The people behind the incidents of the novel wanted to make Harry suffer, figuring he wasn't crazy enough to trigger a full-on war... which he was. The more level-headed members tried to broker peace later [[spoiler:because the war started before all their preparations were complete, preventing a quick victory for the Court]].
* {{Discussed|Trope}} in the Creator/TomClancy novel ''Literature/TheBearAndTheDragon''. China is considering initiating a war of aggression against Russia, and Russian observation planes are staying well within Russian air space, but examining the Chinese preparations. The Chinese war minister recommends shooting down one of the spy planes and stating that it had violated Chinese air space, and then using that as ''casus belli'' for the war. This is never mentioned again, mostly because, thanks to a well-placed spy, China's opponents know exactly what they're doing.
* In the Franchise/StarWarsExpandedUniverse, the Chiss are only allowed to go to war if provoked (i.e. the other guy has to shoot first), so developing a pretext for preemptive strikes [[BatmanGambit becomes a veritable art form]] for the Chiss Expansionary Defense Force. The CEDF wanted to take out the marauding [[PlanetLooters Vagaari]] for decades but were never directly attacked, so in ''Literature/SurvivorsQuest'' they [[spoiler:trick the Vagaari into attacking a Chiss diplomat (and the Skywalkers)]], then into [[spoiler:hitting a major CEDF base]]. They take this ''very'' seriously; in the other half of the story, ''Outbound Flight'', a Chiss Captain intervenes in a fight between the main Vagaari fleet and the titular Republic ship (which he had orchestrated with the help of a Republic smuggler). Despite smashing them utterly with a handful of picket ships, he gets exiled for it.
* Mocked in ''Literature/TenSixtySixAndAllThat'', which names the countries principally involved in fighting and where the fighting took place in UsefulNotes/TheCrimeanWar and UsefulNotes/WorldWarI after describing the incidents that precipitating them involving entirely different countries.

[[folder:Live-Action TV]]
* ''Series/DoctorWho'':
** In the first series of the revival, the Slitheen try to start WorldWarThree so they can [[WarForFunAndProfit sell]] the radioactive remains of the planet as fuel.
** The Silurian captured by the humans in the two-parter "The Hungry Earth"/"Cold Blood" hopes to be killed and tries to get killed, just to start the war.
* This is discussed several times in the mini-series ''Series/{{Attila}}'' (2001). Flavius Aetius presents the young Attila's chief with one of his men who has been tortured as a pretext for taking on a rival tribe. Attila accuses Flavius of having inflicted the torture marks himself as they've been done post-mortem. Later after the chief dies, Flavius warns Attila that he needs a pretext before returning home to take on a rival, so Attila accuses him of murdering the previous ruler. After Attila creates the Hunnic Empire, he uses an earlier offer of marriage by the sister of the Roman Emperor (and half their empire as dowry) to invade their territory.
* When the Romulans in ''Series/StarTrekTheNextGeneration'' aren't trying to destabilize other superpowers, they're trying to lure the Federation into making some blunder that would justify them making a first strike. They actually got pretty close with Picard and a traitor they were stringing along, but Picard hedged his bets and brought some Klingon backup, so they decided it wasn't worth the risk. Aside from the subterfuge being their [[PlanetOfHats hat]], the Romulans go to such lengths because they don't want to be caught in a two-front war with the Klingons, who would provide assistance if the Romulans outright attacked.
* ''Series/{{Rome}}'' between Caesar and Pompey in Season One, and Marc Antony and Octavian in Season Two. Both cases involve CivilWar, so it's important that those seeking war not be seen to incite it, as war against fellow Romans is more difficult to justify than war against foreigners.
* In the 1996 mini-series ''Rhodes'', Cecil Rhodes is planning to invade Matabeleland, currently ruled by the powerful Chief Lobengula. As he's short of finance, he intends paying his army of mercenaries and adventurers with a percentage of the {{Plunder}} (e.g. Lobengula's land and cattle) but fellow businessman Alfred Beit urges against this policy.
-->'''Beit:''' Tear these [contracts] up, for god's sake, and pay your men in cash! Have you thought what this means? The moment one volunteer signs this, there's no turning back. You've got to take Matabeleland. What happens if Lobengula won't play ball? ''What if he absolutely refuses to fight?!'' Are you going to take his country, his cattle, regardless? Never mind the British, you'll have the whole world against you.
-->'''Rhodes:''' Don't worry Beit, he'll play ball.
-->'''Beit:''' ''How can you be sure?''
-->'''Rhodes:''' Because I'll ''push'' him, and ''push'' him until he does.
* In the ''Series/FrontierCircus'' episode "The Shaggy Kings", the renegade Indian Michael Smith tricks Ben and Tony into hunting buffalo on Cherokee lands, and then uses this an excuse to goad the Cherokee into going on the warpath.
* ''Series/MurdochMysteries'': In "Kommando", Major Cole ordered his squad to kill a British family in the Transvaal to stir up anti-Boer sentiment, before launcing an unsanctioned attack on a Boer militia.


* In ''Radio/TheHitchhikersGuideToTheGalaxy'', it says that the history of warfare is divided into three phases: retribution, anticipation, and diplomacy.
** Retribution: Im going to kill you because you killed my brother.
** Anticipation: Im going to kill you because I killed your brother.
** Diplomacy: Im going to kill my brother and then kill you on the pretext that your brother did it.
** There was also the incident where two very tiny alien races were on the brink of war due to a YourMom joke, but what really pushed both parties over the edge was a random comment made by Arthur Dent that traveled through space and time (which happened to be a deadly insult in one of their languages).

* In ''Theatre/KnickerbockerHoliday'', Stuyvesant, GloriousLeader of New Amsterdam, believing that national greatness lies more in guns than butter, suggests that war with Connecticut could be imminent because, he alleges, the Connecticutans have had the cheek to build a fort on the Connecticut River.
* In Shakespeare's ''Theatre/HenryV'', Henry announces to the French ambassador that the Dauphin's insulting gift of tennis balls will be repaid with war, but he has already proclaimed his intention to invade France immediately ''before'' the ambassador's entry -- the Dauphin's insult just gives him an excuse.

[[folder:Video Games]]
* Used in ''VideoGame/ModernWarfare2'', where Vladimir Makarov, a major Russian extremist terrorist, perpetuates a massacre in an airport in the middle of Moscow while Private Joseph Allen, an American CIA agent, is planted in his inner circle. However, Makarov knows about Allen, and the Private is killed and dumped in the airport, and his body used as a pretext by the war-happy Ultranationalists to give them an excuse to invade the United States. The fact that as of ''Modern Warfare 3'' [[spoiler: Makarov appears to be covertly in control of the entire Russian military]] helped sell this.
** This trope is actually active on both the Russian and American sides in different ways. The Russians have been looking for an excuse to go to war with America for years, and are just waiting for a catalyst. Even if the US was completely uninvolved, there's a fairly decent chance they would have blamed the CIA anyway. Indeed, they may have done just that. A well known internationally wanted terrorist is seen, plain as day, strolling into an airport with a machinegun. Even though Allen's corpse is left there, the only thing that would identify him as a CIA agent (or even an American for that matter) is information being fed to the Russian government by a terrorist organization or the game's villain (who are both less than reputable).
** On the American side, this is also an example of [[spoiler:the "hard-line elements from both sides co-operate with each other" example above, since General Shepherd, commander of the US Army Rangers and Allen's superior, was collaborating with Makarov to start a Russo-American war and planted Allen in Makarov's cell for the sole purpose of BEING the catalyst. All part of his plan to reinvigorate America's military might after the nuclear explosion that killed 30,000 Marines in the first ''Modern Warfare'' pacified it. Naturally, once the war actually kicks into gear Shepherd wastes no time [[YouHaveOutlivedYourUsefulness turning on Makarov]], while simultaneously trying to cover up that he was ever involved with him in the first place.]]
* In ''VideoGame/EuropaUniversalis'' you can manufacture claims on another country as a pretext for war using the 'obscure documents' Casus Belli. And in Vicky and Europa occasional border incidents like the pig one occur
** This same system is present in other Paradox Interactive titles, ''VideoGame/VictoriaAnEmpireUnderTheSun'', ''VideoGame/CrusaderKings'', and ''VideoGame/{{Stellaris}}''.
* In ''VideoGame/DragonAgeII'', TheChurch controls all mages and has them guarded at all time by Templars, who will hunt any mage who tries to flee and kill those who show any signs of becoming vulnerable to demonic possession. Since demons offer powers that help a lot in escaping the templars, this actually happens quite frequently. With the templars taking less risks and even sympathising with those who try to escape being treated as being vulnerable to possession, things are constantly getting more dire for mages, but more moderate factions are always intervening to prevent a complete purge of all mages. In a desperate, though brilliant, move [[spoiler:the mage Anders provides a reason for the templars to start a purge immediately without preparation, in the hope that it will unite the mages to fight for their lives, while there is still a chance they can win. He does that by blowing up the local main church with all its priests and publically admiting to the Templars that he did it. When the Templars than used that as an excuse to purge a Circle that their leader knew Anders was never a part of, the resulting outrage from the other Circles kicked off a full-scale war that would finally force the issue to be addressed.]]
** However, going with the game's FailureHero theme, it didn't actually work. The rebellion didn't really spread beyond Kirkwall until [[spoiler: a mad Lord Seeker tried to purge the Val Royeaux circle after a mage murdered a Templar, breaking away from the Chantry which had specifically ordered him not to in the process,]] in ''{{Literature/Asunder}}''.
* ''VideoGame/GalacticCivilizations 2'' has a random event where people from one civ automatically assassinate a very high-ranking politician of another civ, forcing war between the two.
* ''[[VideoGame/{{Civilization}} Civilization V]]'' Ghandi's declaration often involves a couple of troops going "rogue" and attacking your border unprovoked and he just received it. All he could do is simply send kindly worded letters to "withdraw".
** ''Civilization VI'' introduced ''casus belli'' as an actual mechanic. Invoking one when declaring a war reduces the diplomatic penalties received for being a warmonger in the eyes of other civs. The reduction ranges from minor (being honest about commencing a hostile land-grab) to complete negation (reclaiming a declared ally's territory or liberating your own cities carries no warmonger penalty, even if you "technically" declared a new war to recover what you lost in the last one).
* ''VideoGame/StarControlII'' reveals that the human-VUX FirstContact failed not because the human captain off-handedly called his opposite number ugly, figuring the translators weren't working yet, but because the VUX find ''humans'' too ugly to let live. They simply used the "insult" as a pretext to prepare for war. They were conquered by the Ur-Quan and absorbed as BattleThralls, which only worked in their favor.
* In ''VideoGame/StarTrekOnline'' the Klingon Empire uses Undine infiltration of the Gorn as an excuse for stepping up their border war with them into a full-scale invasion, and later retroactively try to use the same excuse to justify attacking the Federation (even though they had openly admitted in the {{backstory}} that they were just after territory).
* ''VideoGame/TheLegendOfHeroesTrailsInTheSky'': As a small kingdom to the south with a pitifully small army and an abundance of [[GreenRocks Septium]] ore, Liberl made an easy target for the Erebonian Empire. Unfortunately for said empire, Civil unrest among the Reformist and noble factions left the government in a politically sensitive position. To tip the scales in their favor, a small village on the border named [[spoiler:Hamel]] was mercilessly butchered down to the last man, woman, and child. The official story [[spoiler:pinned it on Liberlian soldiers, but in fact were Jaegers in disguise]]. This is why several characters in the overall ''[[VideoGame/KisekiSeries Trails]] series have [[DarkAndTroubledPast plenty of trauma to go around]] as the handful of survivors to escape. A deciding factor that ended the war was [[spoiler:the condition that no one on either side was to reveal the truth about Hamel]] as an act of truce. The climax of the ''Second Chapter'' reveals that [[spoiler:the main villain Weisman whispered the name to select people to suggest the idea in the first place, which would give him the opportunity to mold whoever survived into the perfect slave for him to control.]]

[[folder: Web Comics]]
* One arc of ''Webcomic/EscapeFromTerra'' revolves around the United World trying to incite an incident on Ceres that they can use as a pretext for a second invasion attempt (first time they claimed Ceres was rebelling, the natives made it clear Ceres was never part of the UW in the first place). First a few covert ops soldiers go in and try to start a bar fight, but due to the Zero-Aggression Principle most Cereans follow that doesn't work. Then those guys buy a hotel and a small platoon of troops move in, but the locals just accommodate them. And as a last ditch the commissar took a twelve-year old girl hostage and told a prominent local to shoot one of her men disguised as a tourist or the girl would die. [[spoiler: The Cereans instead brought out strippers to distract everyone until they rescued the kid, and the soldiers turned on their political officer.]]

[[folder: Web Original]]
* ''VideoGame/ImperiumNova'' has a {{feud|ingFamilies}} system. When one House engages in actions against another House such as withholding taxes, insulting dynasty members, espionage (and are caught), or attacking facilities; the offended House gains feud points that can be spent attacking the offender. If a House attacks another House, on a planet under Imperial Jurisdiction, without feud the Emperor declares them a Renegade, which allows every other House to attack them with impunity.
* In the ''Literature/NewDealCoalitionRetained'' timeline, a firefight at the inter-German border in 1988 -- caused by overzealous West German guards stepping in when the East Germans execute refugees attempting to flee across the border -- serves to set off the powder keg that international relations have been ever since [[TheCoup the December Coup]], sending the world spiraling to WorldWarIII. [[spoiler: Which is what the hardliners in Moscow want, as they see war as the only way to revitalize their economy. Hence why they sabotage diplomatic efforts to soothe matters by giving demands they know the West will reject.]]

[[folder:Western Animation]]
* In ''WesternAnimation/DragonsRidersOfBerk'', [[MeaningfulName Dagur the Deranged]] visits Berk, having heard a rumor that they have taken to training dragons. It is heavily implied that Dagur wants to use that fact as an excuse for the Berserker tribe to wage war on Berk.

[[folder:Real Life]]
* That pig thing, in the trope discription? [[https://en.wikipedia.org/wiki/Pig_War_(1859) It was real.]] It wasn't much of a war though: "The pig was the only casualty of the war, making the conflict otherwise bloodless." from Wiki/TheOtherWiki. The situation was diffused largely because the commanders of both sides flatly refused to fight over something so stupid.
* [[http://en.wikipedia.org/wiki/War_of_Jenkins%27_Ear The War of Jenkins' Ear]]. The British had managed to get themselves exclusive rights to trade slaves in the Spanish colonies in America, but at the cost of Spanish crews being allowed to board British ships and search their cargo. Relations became rather strained, and then a one-eared merchant captain by the name of Jenkins showed up in Parliament with a severed ear and a story of Spanish brutality that sparked the above war. It is doubtful as to whether the ear exhibited in Parliament was actually Jenkins' lost ear, as historians today and his contemporaries believe that he lost his ear in a bar fight years before.
* UsefulNotes/WorldWarI. The assassination of the heir to the Austro-Hungarian throne, Archduke Franz Ferdinand, by Serbian terrorists sponsored by the head of Serbian military intelligence to further the goal of Serbian dominance of the Balkans was used as an excuse to take down Serbia's racist military Junta and replace it with a government which ''didn't'' sponsor terrorists (even during the war there was no question of annexing Serbia, as doing so would only have added to Austria-Hungary's domestic political problems). Which sounds a bit unreasonable until you realise that the very existence of Serbia (an independent nation-state of ethnic Serbs whose sole foreign policy goal was to unite all the lands inhabited by Southern Slavs into Yugoslavia, which they envisioned as as a Greater Serbia) terrified the German/Hungarian elites that ruled the mindbogglingly multi-ethnic Austria-Hungary. Right from the start they thought that, with Germany backing them all the way, Russia would back down rather than risk war with them ''and'' Germany at the same time, just like six years earlier over the formal annexation of (Habsburg-occupied, technically Ottoman) Bosnia.
** For reference, the main ethnic groups in Austria-Hungary were, roughly by population: Germans, Hungarians, Czechs, Poles, Ukrainians, Croats, Slovaks, Serbs, Slovenes, and Italians. Plus a lot of Jews, most of whom spoke German/Yiddish or Hungarian.
** Furthermore, right from the start the German High Command's accepted plan of action was to use ''Aufmarsch I West'' (formerly ''Aufmarsch II West''), deployed 80% of the army in the west to invade France through Belgium and attempt to encircle a large part of the French Army on French territory (failing that, they'd still end up occupying economically important French territory). So when Russia mobilized its armies Germany delivered an ultimatum to France as a pretext for war, demanding its neutrality despite being an ally of Russia and asking it to temporarily surrender fortresses integral to France's defenses (Verdun and Toul) along their shared border within 24 hours. The French didn't respond but mobilised the next day, as did the Germans; since about 1911 the ''Revanchism'' movement, a movement seeking revenge for France's defeat in the Franco-Prussian War and the re-annexation of the province of Elsaß-Lothringen (Alsace-Lorraine) had become a dominant force in French politics and was not to be denied. More importantly the French felt that this was an excellent time for a war: deadlock in the German and Austrio-Hungarian parliaments meant they hadn't increased their military spending and thus capabilities to match the 1905-1914 Franco-Russian increases, but that was set to change in the near future. Moreover the French did not feel they could count on Russian support in a war that mostly or only involved French (and not Russian) interests. Serbia was a cause that Russia was willing to fight for, and the French might not get another chance like it again.
*** Or to make a long story short, a bunch of people wanted some stuff and threatened to go to war if they didn't get it, but mostly wanted a war. Some other people didn't want to give it to them but kind of wanted a war too. One thing led to another and there was a war, which everyone thought would be over in about three months (with their side victorious, of course). And then it snowballed into a really, really big war. Then about six months later, they all thought to themselves, "Why the hell did we do that?" But by then, they were committed.
* The [[http://en.wikipedia.org/wiki/Shelling_of_Mainila Mainila incident]], which the Soviet Union used as a pretext for invading Finland during the Winter War. It has been established that there is no way the Finns could have been responsible, as none of their artillery was in range at the time. See FalseFlagOperation.
** A few months later, the Soviets started claiming that the Baltic states captured and are torturing some of their soldiers. Remembering Finland, all three countries agreed to join the USSR. No attempt to find the captive soldiers followed.
* Similarly, the [[http://en.wikipedia.org/wiki/Gulf_of_Tonkin_incident Gulf of Tonkin incident]], in which an American ship on patrol claimed to have been attacked by Vietnamese gunboats, serving as a pretext for UsefulNotes/TheVietnamWar; but the reports may have been fabricated to gain popular support for escalating military operations in Southeast Asia.
** It's a little more complicated. There were actually two "Gulf of Tonkin" incidents, separated by around 48 hours. The first incident took in disputed waters, claimed by North Vietnam as its territorial waters but by the US as international waters, conveniently not too far from an area where a South Vietnamese covert operation against the North was taking place. (North Vietnam claimed that US warships were supporting it, while US has denied it.) During this incident, which was very real, North Vietnamese patrol boats took the worst of it, while US warships suffered nothing more than a few dents. The second incident took place in the middle of night, roughly 40 hours later, in undisputed international waters. Sailors onboard US warships (which were involved in the first incident) thought that they were under attack by North Vietnamese and spent most of the night shooting at something...or nothing. Military intelligence officials who received the report thought the whole thing was a mistake by confused sailors and no actual attack took place--which has been confirmed by every investigation thereafter by military, government, academics, etc. But Johnson administration decided to ignore the intelligence report and assert that the second attack was real to justify escalating conflict.
* To make a trifecta, the sinking of the ''[[http://en.wikipedia.org/wiki/USS_Maine_%28ACR-1%29 USS Maine]]'' in Havana Harbor provided America with the perfect excuse to start the UsefulNotes/SpanishAmericanWar and take over Cuba and Spain's Pacific possessions. Investigations since then seem to be split on whether it was a deliberate act of war by the Spanish, a FalseFlagOperation by Cuban rebels, or a genuine accident caused by a fire in a coal bunker.
** It didn't help that the American press was actively encouraging war with Spain by citing (false) Spanish atrocities. Why? [[IfItBleedsItLeads To increase their sales figures]].
* Another FalseFlagOperation was the Mukden Incident of 18 September, 1931, in which the Japanese officers faked an explosive attack on the South Manchurian railroad to spark off the Manchurian Crisis.
** Another escalation of the Japanese war in China start with a Japanese soldier peeing in the woods. Seriously - he missed role call after training while taking a leak, and his commanding officer challenged a nearby Chinese patrol, thinking the man might have been abducted or attacked by the Chinese. Tempers flared and somebody (from which side is not known) opened fire. Things were nearly smoothed over by the local commanders, but the Japanese Army high command refused to de-escalate as they had been looking for any old pretext to expand into more of China anyway.
* The revolution that led to the Republic of Colombia becoming independent was supposedly triggered by "El Florero de Llorente" (the vase of Llorente), which was a trick by the supporters of the independence to upset a Spanish merchant and incite the crowd against the Spanish people. This led to a popular expression used when you need a excuse to start a fight.
* The [[http://en.wikipedia.org/wiki/Gleiwitz_incident Gleiwitz Incident]] was used as a pretext for Germany's invasion of Poland in 1939. An SS commando in Polish uniforms attacked a radio station near the Polish border and broadcast anti-German propaganda. They even dressed a prisoner in Polish uniform and shot him to add authenticity.
** It was actually bigger than people think. During the summer of 1939, the Nazis staged attacks on ethnic Germans in Poland, claiming this was the work of Polish terrorists.
* The [[http://en.wikipedia.org/wiki/Football_War Football War]] had a ''football match'' as part of its pretext.
* Lampshaded in the [[http://en.wikipedia.org/wiki/Louisiana_Maneuvers Great Louisiana Maneuvers]] of 1941. These were held to [[TeachMeHowToFight prepare the US Army]] for the widely expected entry into UsefulNotes/WorldWarII and in a way marked the beginning of the United States as a superpower. Two trumped up factions called the Red Army and the Blue Army were set to test their prowess against each other. To begin the contest it was decided that they represented two nations fighting for control over the Mississippi River.
* There's a conspiracy theory that 9/11 was a FalseFlagOperation by the Bush administration in order to provide a pretext for invading Iraq. Leaving aside the part where [[http://www.cracked.com/article_15740_was-911-inside-job.html the whole thing started life as a work of fiction]], the correct response for someone too bored to counter with hard data is to invoke the names of {{Occam|sRazor}} and {{Hanlon|sRazor}}.
** FalseFlagOperation aside, there is compelling evidence to suggest that 9/11 was used to justify a first-strike in Iraq for reasons varying from personal (such as removing Saddam Huessein from power) to financial (such as [[CorruptCorporateExecutive taking all of Iraqs oil and getting filthy rich]]).
** 9/11 aside, the main pretext for war as sold to the public was the Iraqi government failing to hand over it's hidden chemical weapon stockpiles. Weapons it would later turn out they did not actually possess.
** An alternative conspiracy theory holds that al-Qaeda were the perpetrators, but claims the government knew the attack was coming and did nothing to gain an easy pretext. Another unrelated theory says UsefulNotes/FranklinDRoosevelt was aware of the impending Pearl Harbor attack and let it happen for the same reason.
* UsefulNotes/TheCrimeanWar started thanks to a dispute between Catholic and Orthodox clergymen in Bethlehem (present-day Israel, then part of the Ottoman Empire), over the keys to the Church of the Nativity. This led to the awkward situation of Catholic France and Anglican Britain siding with Muslim Turkey against Orthodox Russia over a religious argument.
* In the runup to the Six Days War, Nasser was either intentionally provoking Israel or blustering to look tough. First he called for an end to the UN mission acting as "buffer" between Egypt and Israel in the Sinai, then he started mobilizing troops, ostensibly in preparation for war - all while saying stuff like "We'll destroy Israel" on the radio - and ultimately, he closed the Straits of Tiran,[[note]]Israel's only access to the Red Sea and of crucial importance for Israeli trade with Asia[[/note]] which Israel had ''repeatedly'' said would be [[ThisMeansWar grounds for war]]. Guess what happened?
* In perhaps one of the most poorly thought out attacks in history, the Japanese attack on Pearl Harbour during World War II was intended to scare the US into remaining neutral rather than joining the Allies. Of course, the US had been aiding the allies with supplies for years at that point and had been desperately searching for a reason to justify entering into the war in a military capacity. This was less about justifying it internationally -- the other Allied forces were happy to have the US join the fight and would not have complained regardless of the pretext -- and more about justifying it domestically, since public opinion within the US was fairly split about whether they should enter the war. Then the Japanese attacked and any resistance to joining the war evaporated as now it would look worse NOT to retaliate.