Fallout canon refers to elements considered an official part of the Fallout universe. As the Fallout series was developed by multiple development studios (the Fallout development team first, then Black Isle, Microforte, Bethesda Game Studios, and Obsidian Entertainment), the general lack of overlap between development teams has caused numerous inconsistencies to emerge. Compounded by different opinions on certain elements of the setting among the developers (such as Tim Cain and Chris Taylor disagreeing on the origins of ghouls), this necessitates certain assumptions on part of anyone covering the game.
Since the acquisition of the Fallout franchise by Bethesda Softworks and their development of Fallout 3, Bethesda defines the canon of the Fallout series. However, Bethesda has refrained from issuing an official statement on what is canon and what is not. The following list is considered to be the most representative of the company's stance on the subject, according to available information.
Primary sources are officially released works that form the core of the Fallout franchise and setting. Primary sources include:
- Fallout and supplementary materials,
- Fallout 2 and supplementary materials,
- Fallout 3, its add-ons, and supplementary materials,
- Fallout: New Vegas, its add-ons, and supplementary materials, including All Roads,
- Fallout 4, its add-ons, and supplementary materials,
- Fallout 76 and supplementary materials,
Secondary sources are works, publications and other materials (such as developer interviews, responses on social media sites, forum posts, et cetera) that build upon the Fallout setting, but do not belong to the "core" of the franchise. In case of contradicting information, primary sources take precedence.
- Fallout Shelter is a spin-off free-to-play game. Material from the game can be considered part of the setting if it isn't contradicted by existing sources (such as with the number of Vaults). The Vault-Tec Workshop add-on also made a large part of Fallout Shelter content canon, such as certain dialogue and rooms.
- The Fallout Bible by Chris Avellone. Todd Howard has mentioned it as being part of the source material Bethesda reviewed as part of the Fallout 3 creation process. Emil Pagliarulo has also stated that he used it during development. Finally, several setting elements introduced exclusively in the Bible have been further developed in Fallout 3, Fallout: New Vegas, Fallout 4, and Fallout 76.
- Note: Chris Avellone is of the opinion that the Bible shouldn't be used as canon and that Bethesda is not limited by its contents. However, the current owner of the franchise and thus, only authority on Fallout canon has not clarified the Bible's status, apart from statements by Emil Pagliarulo and Todd Howard mentioned above as well as elements incorporated in released games.
- Fallout Tactics, when referenced by existing titles, can be considered a secondary source. Even then, it is limited to high level events (as explained by Emil Pagliarulo to our founder). However, it should also be noted that in a 2007 interview with Todd Howard, he stated, "For our purposes, neither Fallout Tactics nor Fallout: Brotherhood of Steel happened." Currently, the only events referenced in the game are the presence of a small, rogue detachment of the Brotherhood in Chicago that has been battling super mutants in the city (a retcon of Tactics, where super mutants were fought in Missouri, starting with St. Louis), and arrived there by airship.
- Note: The reference to super mutants in Chicago is an explicit retcon, as the super mutants in Fallout: Tactics were fought first at St. Louis, more than 250 miles south of Chicago.
- Some elements of Van Buren (the canceled Fallout 3 by Black Isle Studios) were incorporated into Fallout 3 and its add-ons, as well as into Fallout: New Vegas and Fallout 76, making them part of the current Fallout canon.
- Except for the above, Fallout Tactics and its tabletop component, Fallout: Warfare, were disregarded by Bethesda Softworks during the development of Fallout 3.
- Fallout: Brotherhood of Steel is treated as non-canon by Bethesda Softworks.
- Canceled games, such as Van Buren, Project V13, Fallout Extreme, Fallout Tactics 2 and Fallout: Brotherhood of Steel 2 are non-canon, unless aspects of these games are confirmed by other canon sources.