Updated October 12, 2017: Continuity nerds, alert - Marvel Studios has plans to publish an official timeline to the Marvel Cinematic Universe. Spurred on by some continuity questions brought up in Spider-Man: Homecoming, studio president Kevin Feige has announced plans for an "official" timeline to be published.
"All of that debate has encouraged us. We are going to be publishing an official, and I’m not sure when, or in what format, an official timeline," Feige told CBR. "It’ll probably be apart of ah, I don’t know, apart of an in print that you can fold out and look at. But suffice to say, only in limited cases do we ever actually say what the actual years are because we never want to be tied down to a particular year and I think people assume that whenever the movie is released is when is when the movie is taking place, and that is not the case."
Back in June 2017, Spider-Man director Jon Watts confirmed that an official timeline document was in-use inside Marvel Studios' offices.
Original Story: Marvel Studios has a timeline for their films that stretches far into the future - and the past. No, we're not just talking about their release schedule - according to Spider-Man: Homecoming director Jon Watts, there's an official document that covers then entire history of the Marvel Cinematic Universe.
“There’s an actual scroll that they unrolled for me,” Watts told Entertainment Weekly. “One of my producers, Eric Carroll, it was his first job at Marvel to work on a timeline and see where things line up and see where things didn’t quite line up. Like, ‘Oh, that’s when Captain America is born.'”
"It’s very long. It’s the most amazing thing because it starts, honestly, at the beginning of time — I don’t remember specifically, but I think it has something to do with Thor. It is truly an amazing document.”
In all fairness to Watts, that was probably Thor's grandfather Bor, as seen in Thor: The Dark World.
Spider-Man: Homecoming is due out in theaters July 7.