Canon Invasion is when two unrelated titles are originally owned by two different entities but are forced into the same fictional universe after one buys the rights from the other. Sometimes, it's immediately after; other times, it's CanonWelding belatedly kicking in.

The "Invaders" bring their own, possibly conflicting, continuity with them; and since they didn't originate with the same creator, the differences will likely be more severe than with CanonWelding. Expect {{Retcon}}s, especially if the invaders are inserted directly.

Because of the Continuity issues, Canon Invasion may turn TheVerse into TheMultiverse as its first effect (if the original 'verse wasn't already a multiverse), especially if there are huge differences in the laws of metaphysics. The original canon characters are in one universe, and the newer ones in another, and now there is a bridge between them. Thus, Canon Invasion is sometimes less disruptive than CanonWelding.



[[folder:Comic Books]]
* In Franchise/TheDCU:
** Going back to UsefulNotes/TheGoldenAgeOfComicBooks, even characters such as Franchise/{{Superman}}, Franchise/{{Batman}} and Franchise/WonderWoman were initially not thought of as being part of the same continuity.
** ComicBook/TheQuestion, ComicBook/BlueBeetle, ComicBook/CaptainAtom and others started out in Creator/CharltonComics before being sold to Creator/DCComics. In fact, ''ComicBook/{{Watchmen}}'' was going to use them as its characters, except DC actually wanted to be able to use them again later. Hence the team of {{Captain Ersatz}}es instead.
** The same goes for the Fawcett characters (the ''ComicBook/{{Shazam}}!'' Captain Marvel and the Marvel Family), and the Quality Comics characters (ComicBook/PlasticMan, the Comicbook/{{Blackhawk}}s and the Comicbook/FreedomFighters (the rest are {{Public Domain Character}}s))
** They did this again with the ''Red Circle'' -- a series of one-shots that brought old Franchise/ArchieComics superheroes the Hangman, Inferno, Shield and Web into Franchise/TheDCU. Unlike the above examples, DC didn't buy the Red Circle characters - it merely licensed them for a few years.
*** This has now been done again, the difference being that the characters are now brought into DC's mainstream universe.
*** DC's back to not referencing them due to Archie getting the rights back and because of the Reboot.
** Milestone Media, the creators of the Creator/MilestoneComics line (including ''ComicBook/{{Static}}''), originally had them published via DC Comics, but as their own distinct universe. DC eventually struck a deal with Milestone to bring the characters into the DCU proper, as well as the ''WesternAnimation/StaticShock'' TV show getting pushed into Franchise/TheDCAU. Later on, they struck another deal so that Milestone would be its own distinct universe again, this time as part of the DC Multiverse.
** The Creator/{{Wildstorm}} Comics universe. Originally part of a loosely-defined Creator/ImageComics universe, Wildstorm was integrated into the DCU {{Multiverse}} as "Earth-50" with a series of crossovers involving Franchise/{{Superman}}, [[ComicBook/WildCATs Majestic]], and ComicBook/CaptainAtom.
*** And then Comicbook/{{Flashpoint}} brought Wildstorm into Franchise/TheDCU as well.
* In the Franchise/MarvelUniverse:
** Although technically always owned by the same company, ''ComicBook/TheEternals'' at Marvel is otherwise an example. The series was created by Creator/JackKirby as separate from the MarvelUniverse, but later brought into it, with the result that, for instance, there would be Marvel Universe versions of gods but Eternals who were posing as those same gods.
*** This was [[LampshadeHanging lampshaded]] in an issue of ComicBook/TheMightyThor where it was revealed The Eternals and The Olympians had made a pact so the former would "represent" the latter in front of mortals.
** Also Machine Man originally appeared in issue #8 of Kirby's monthly comic of ''2001: A Space Odyssey'' where each issue a different person encounters the 2001 monolith. Machine Man later got his own series and was integrated into the Marvel Universe.
*** Many references from the movie were [[{{Rewrite}} rewritten away]]. However, it is sporadically mentioned that the creators of the monoliths were [[spoiler:the Celestials]].
** Marvel bought out Malibu Comics in 1994 and soon Marvel heroes and villains were cropping up in Malibu titles. However, Marvel soon canceled all of the Malibu titles and common fan speculation was that Marvel only bought the company to acquire Malibu's then-groundbreaking in-house coloring studio, and/or its catalog of easily movie-licensed properties. Within the Marvel Comics multi-verse, the Malibu Universe is now designated as Earth-93060.
** Believe it or not, when Marvel briefly had the rights to publish Franchise/{{Godzilla}} comics, Big G himself was a character in the Marvel Universe. And ''it's still considered 616 canon!''
** Even though ComicBook/RomSpaceknight can't be referenced, all the supporting characters and villains can still be seen in comics and the series is still canon.
** Aside from actually calling the ComicBook/{{Micronauts}}, the Micronauts, all the characters created for the comic can still be used and are all canon. Hell the character Bug was a member of the Comicbook/GuardiansOfTheGalaxy and Captain Universe nearly killed Juggernaut in a Spider-Man comic.
** While ignored later on, Spider-Man appeared in early issues of Marvel's [[ComicBook/TheTransformers Transformers]] series, which made the Autobots and Decepticons {{Canon Immigrant}}s to the Marvel Universe, at least temporarily.
*** Technically the Marvel Transformers comics took place on alternate universes (Earth-91274 for the American comics and Earth-120185 for the UK comics) and are a huge part of the character ComicBook/DeathsHead origin, so the Transformers comics are very loosely canon.
*** But don't ask where Earthforce fits in as not even Marvel or Hasbro will attempt to make it [[CanonDiscontinuity canon]]. These are the companies where Marvel WhatTh--?! and Transformers: Kiss Players are to some degree canon.
** ''Franchise/EvilDead'' fits in here as the Dynamite ''Comicbook/ArmyOfDarkness'' comics got referenced in the ''ComicBook/MarvelZombies'' crossover and numbered in an issue of The Offical Handbook to the Marvel Universe.
** ''Franchise/{{Doctor Who|ExpandedUniverse}}'' is arguably canon if only because the Doctor has crossed over with Death's Head, Marvel's version of Merlin, and the obscure Creator/AlanMoore superteam Special Executive who first appeared in ''Magazine/DoctorWhoMagazine'' before appearing in ''ComicBook/CaptainBritain''.
** Licensed Robert E. Howard characters are probably the most firmly fit into the MarvelUniverse. For example Conan (major enemy of Kulan Gath, enemy of Set a serpent god who powers the Serpent Crown, and ally to Comicbook/RedSonja who would crossover with Spider-man twice), King Kull (who ruled over Namor's Atlantis in pre-history), and Solomon Kane (appearing in back up stories in Savage Sword of Conan, as well as getting his own mini-series.)
*** Shuma-Gorath was also an enemy of Conan's god Crom.
** Literature/FuManchu is Shang-Chi's dad. That is all.
** ''U.S. 1'' is canon to the MarvelUniverse.
** Marvel's Guardians of the Galaxy/Killraven continuity's entire premise is that after the Martians of ''Literature/TheWarOfTheWorlds'' failed to conquer Earth the first time, they came back in 2001, and basically killed almost every super hero with only freedom fighters left to defend Earth.
** Earth-7642 of the Marvel Multiverse is the universe for all the crossovers that act as if characters crossing over with Marvel were part of continuity the whole time. It consists of most of the 70's to 90's crossovers with DC Comics, the IDW version of Transformers, Shi, VideoGame/{{Painkiller}}, many Creator/ImageComics and Top Cow characters, Franchise/ArchieComics, and a few [=WildStorm=] characters.
** Subverted in the case of the Marvel Franchise/DocSavage comics, which didn't last long and the only proof of Doc existing in Earth-616 is him crossing over with the Thing and Spider-Man.
** This ''almost'' happened on an unimaginable scale in the mid '80s, when for a brief moment, DC seriously considered getting out of the comics publishing business and licensing all of their characters to Marvel. DC and Marvel engaged in talks, and a deal was almost struck when higher-ups on both sides called a halt. Had it happened, though, Superman and Batman may have inhabited New York alongside Spider-man and The Punisher, and the Justice League and the Avengers would have had to negotiate turf.
*** Actually, in the comments on his blog Jim Shooter says the plan was to keep them separate, at least at first.
** Another Guardians of the Galaxy one: Image character Angela got pulled into 616 by the events of ''Comicbook/AgeOfUltron'', and joined up with the Guardians. [[spoiler:She has since been retconned into Thor and Loki's long-lost sister]]
* Creator/ValiantComics continuity was made up of original characters and licensed [[UsefulNotes/TheSilverAgeOfComicBooks 1960s]] characters that were originally published by Creator/GoldKeyComics. Furthermore, the licensed characters, which originally existed in separate continuities, were retroactively linked together, forming the basis for the rest of the shared continuity.
* ''ComicBook/TwoThousandAD'' absorbed a similar SF based comic called ''Starlord'' in the 1980s. The only ''Starlord'' strips that stuck were ''ComicBook/StrontiumDog'' and ''Ro-Busters''. The backstory of ''Strontium Dog'' has been absorbed into the same continuity as other ''2000 AD'' strips and there have been crossovers with ''ComicBook/JudgeDredd'', even though it happens after a nuclear war which is yet to occur in Dredd's universe.
* The short-lived Semic Comics universe took characters from two different French publishers and combined them all into a single integrated continuity, which is quite a feat considering almost all the characters involved were originally unrelated to each other.
* Several non-player characters in the ''Roleplay/GlobalGuardiansPBEMUniverse'' are direct lifts from DC and Marvel Comics, including Hawk, Dove, Cloak, Dagger, and Uncle Sam.

[[folder:Live-Action TV]]
* Originally NBC's ''Series/{{Constantine}}'' was completely unrelated to CW's "Series/ArrowVerse" (consisting of ''Series/{{Arrow}}'', ''Series/TheFlash2014'' and ''Series/LegendsOfTomorrow''), but it was later stated to be part of the verse with Matt Ryan reprising his role as the titular John Constantine in the fourth season of ''Arrow''.

[[folder:Tabletop Games]]
* Creator/PalladiumBooks is best known for their flagship line, ''TabletopGame/{{Rifts}}'', but they also have the license to produce the ''Anime/{{Robotech}}'' RPG. This one is used inconsistently; Robotech is canonically in the [[TheMultiverse Megaverse]], and there are rules (down to technical specifications) for [[CrossOver crossing Robotech characters and mecha over into Rifts]], but it hasn't actually happened in official material. Since Palladium published ''TabletopGame/TeenageMutantNinjaTurtlesAndOtherStrangeness'' for a while, that too is in the Megaverse.

[[folder:Video Games]]
* ''[[VideoGame/DynastyWarriors Warriors Orochi 3]]'' features characters from ''VideoGame/NinjaGaiden'' and ''VideoGame/DeadOrAlive'' as a result of Creator/{{Koei}}'s merger with Creator/{{Tecmo}}, becoming Koei Tecmo Games.
* ''VideoGame/ItadakiStreet Special'', a [=PS2=] entry in Enix's computer board game series, was the first game since the Creator/SquareEnix merger to feature characters from both the ''VideoGame/DragonQuest'' and ''Franchise/FinalFantasy'' franchises.