Some spoilers here, but it's impossible to discuss what's going on without them, as the end of Captain America: Civil War sees Steve Rogers aka the Cap'n himself putting down his shield and walking off into the metaphorical sunset. Fans have wondered that that means for both Captain America and the Marvel Cinematic Universe going forward, and while we don't have any answers on the latter, an interview with the directorial duo the Russo Brothers via The Huffington Post has confirmed our worst fears: The Captain is the Captain no more.
"I think him dropping that shield is him letting go of that identity,” said co-director Joe Russo in the interview. “[It’s] him admitting that certainly the identity of Captain America was in conflict with the very personal choice that he was making.”
So that's it. Steve Rogers is no longer Captain America. That doesn't necessarily mean that Steve Rogers won't be in future Marvel films, though. While Chris Evans' contract with Marvel has run its course, there's nothing preventing him from signing another one if Marvel wants him back. One theory for Rogers' future involves him taking up the mantle of Nomad, which he also does in the comics when he learns that the President of the United States is the leader of an evil organization known as the Secret Empire.
Of course, Marvel could decide to move in a totally different direction, allowing someone else to take up the mantle of the Captain, at least for a while - there's certainly precedent for this in the comics as well. And Chris Evans' IMDb page is surprisingly bereft of in-production Marvel Cinematic Universe projects.
Whatever path Marvel decides to take, we probably won't find out more about the ultimate fate of Steve Rogers until we get closer to Avengers: Infinity War, with Part One coming in May 2018 and directed by the Russo Brothers.