The moment Samuel L. Jackson's Nick Fury walked out of the shadows after the end credits of Iron Man, the Marvel Cinematic Universe was created.
So why is the glue behind the Avengers and most of the Marvel movies' not showing up in the most superhero-studded movie of the century,Captain America: Civil War?
Not even Samuel L. Jackson knows. He told Collider (via Hollywood Reporter):
"I'm not in 'Captain America 3.' I can't figure that out, but I'm not. I guess I'm still out there, trying to figure out what happened to S.H.I.E.L.D. and who these other people are."
That seems odd, considering Fury is so strongly allied to the Avengers and even seems to be running their base at the end of Avengers: Age of Ultron. So in a movie that's basically being billed as "Avengers 2.5," it doesn't make much sense not to have Jackson in the movie, for at least a short appearance.
And yes, the movie seems to be overcrowded enough as it is, with most characters other than Captain America and Iron Man likely to have little screentime, but it seems like it would be harder to explain away Nick Fury's absence when he plays such a pivotal role in running the new Avengers team (who are all confirmed for Civil War, by the way).
(tumbler.com)
It may be a contract issue, as Jackson only has two Marvel movies left in his contract, and Marvel may be saving him for the big Infinity Wars two-parter. However, Jackson told Collider that he's "looking to re-up" his contract, and maybe squeeze in a few more movies in there.
But until whenever we see you again, Nick Fury, you will be missed.