10 Huge Differences Between Marvel Movies And The Comics
4. The Events Of Civil War

For the most part, the Marvel films have taken a loose approach to the continuity they're adapting, often cherry picking from various different stories and putting their own spin on it. The Captain America films have bucked that trend though by focusing on specific stories like The Winter Soldier and Civil War for their namesake films. However, that doesn't mean they've been afraid to make some alterations.
Out of the two, Civil War went through the biggest changes. Firstly, the conflict was reduced considerably from a fight between every hero in the Marvel Universe to a conflict just between the Avengers to accommodate the MCU's far smaller cast of heroes.
The event that incited the war was also radically different. In the comics, it was the controversial actions of the New Warriors trying to take on the supervillain Nitro, actions which led to their deaths and the destruction of the town of Stamford. In the film, this was scaled down to a general concern over the Avengers and their lack of oversight.
Another change is that Baron Zemo had no role in the Civil War. And that's not the only thing that was changed about Helmut Zemo.