The Marvel Cinematic Universe has gone through the Infinity Saga, is currently in the Multiverse Saga, and is now fielding rumors of a Mutant Saga. The catalyst for such talk is Deadpool & Wolverine, the multiversal epic that brings Deadpool into the MCU. But he doesn’t come alone. Along with Wolverine, the movie brings characters from every Fox Marvel movie into the MCU... with a catch. As was hinted at in The Marvels’ post-credits scene, that entire cinematic universe exists on a timeline running parallel to the MCU... and now we know exactly where it is.
In Deadpool and Wolverine, we learn that Loki's TVA refers to the world of the Fox Marvel Movies as Earth-10005, which differentiates it from the “Sacred Timeline,” Earth-616. This isn’t a new term. Just as Earth-616 was established in the MCU as the main timeline, Earth-10005 was named in 2008’s Official Handbook of the Marvel Universe A to Z as the world where the X-Men movies take place.
The X-Men universe has several contradictions, so there are issues with lumping them all into one timeline. But the MCU has already handwaved away a lot of its continuity problems with multiversal hijinks or well-placed meta-references.
Bringing Earth-10005 into the MCU adds it to a long list of alternate universes, including Earth-838, the universe where we saw Charles Xavier and the Illuminati in Doctor Strange in the Multiverse of Madness, Earth-688, the home universe of Venom seen in the post-credits scene of Spider-Man: No Way Home, and the countless alternate realities seen in What If. For now, you can rest assured that if you’re watching an X-Men movie, it’s set in Earth-10005, a timeline that drew the TVA’s interest in Deadpool & Wolverine. So the X-Men are now officially in the MCU... kind of.
