In the comics, things didn't end too well for a certain Steve Rogers during Civil War. After losing the war against the pro-registration side of the Marvel Universe, Captain Americasurrendered and was set to stand trial for his "crimes" against the country in leading a group of heroes to fill out the anti-registration side of things. As Steve was led to the courthouse, shots rang out and his lifeless body fell to the ground. For a time, his former sidekick, Bucky, took up the stars and stripes and was Captain America for a number of years before the original Cap returned. Cap's resurrection was a little out there (as he had actually been shot with "time bullets" as part of a plan concocted by the Red Skull), but his death rang heavy throughout the Marvel Universe and was something of a surprise as it hadn't even taken place during the main Civil War title, but rather as an afterthought.
With the film version dropping next year in the form of Captain America: Civil War, will things repeat themselves? Is Chris Evans' portrayal of the character set for the grave as the credits role? Let's look at some ideas behind why this may very well be the case as to Steve giving his final bow in the Marvel Cinematic Universe, with the first being Chris Evans himself. The Marvel Cinematic Universe is a testament to Marvel Studios' ability to employ actors for quite some time in weaving together a massive storyline between multiple films, but all good things must come to an end unfortunately.
Chris Evans has debated retiring from acting in the past, spending more of his time in the director's chair, rather than slinging a shield. In recent interviews though, he's been somewhat 50/50 sometimes stating that he'd always be a "company man", stating that he'd be the Captain for as long as Marvel/Disney wanted him. While it certainly seems like he'll be Captain America for some time, age has to catch up to him at some point. I'd bet dollars to donuts that Marvel Studios has had numerous discussions about whether to have Steve Rogers be Captain America for the foreseeable future. Considering the original end to Civil War in the comics, this could be a good time for Captain America to bite the big one, creating an environment for the Marvel Universe that would be much darker than what we had seen so far, outside of the Netflix fare of course.
Were Captain America to die in the Civil War film, this isn't necessarily to say that he'd be permanently done for however. This is the Marvel Universe after all and Bucky was long considered a character who would never return from the grave, and yet here we are! They could go with the "time bullet" storyline again, injecting a new way to bring back Red Skull into the fold, or they could resurrect Cap in Avengers: Infinity War. With the Infinity Gauntlet, anything is possible and one of the major caveats of that story was having all the heroes die and come back to life once Thanos was defeated. This could be another avenue to eventually bring back Rogers if he were to kick the bucket. I wouldn't necessarily think that if Cap died next May, we'd see the last of the character, after all, we still need to see him lift Thor's hammer!
Whether Steve lives or dies, I think Civil War will cause some serious ripples in the Marvel Cinematic Universe, breaking new ground for the arrivals of Spider-Man, Dr. Strange, and Black Panther into the mix to name a few.