With 1989's Glory, director Edward Zwick, working with a screenplay by Kevin Jarre (which was based on two different books) and the letters of a Civil War colonel, created an incredibly memorable look at the 54th Regiment of Massachusetts. The regiment is notable for being the first African American regiment to fight for the North. The tale that Zwick puts forth is strong on character (even if many of them are composites), story, and heartfelt emotion.
The film opens with Robert Gould Shaw (Matthew Broderick) fighting at Antietam, and afterward returning home to Massachusetts. It is there where the notion behind the 54th is explained to him, and where he is offered its command. Though initially hesitant, Shaw accepts the command and gets his friend, Major Cabot Forbes (Cary Elwes), to accept a position as second in command of the regiment.
Much of the film is spent showing how Shaw, a very by-the-book leader, not only molds his men into soldiers, but how they mold him into a better human being. In leading his men, Shaw is depicted as possibly harsh, but always doing the best that he knows how to do for those he commands. The men under his command, including Forbes, vehemently disagree with some of his actions in training the 54th, but there is never a doubt in the film that Shaw is a good man — he simply needs to learn better how to deal with people from a different background than his.
Shaw begins to understand things as his pays more attention to those under his command, particularly John Rawlins (Morgan Freeman), who is eventually elevated to Sgt. Major of the regiment, and Private Trip (Denzel Washington in a role which won him an Academy Award for Best Supporting Actor). Rawlins is the wise, older, sensible man who understands the realities of the war and the world but still believes in good, whereas Trip is the hard-headed, angry young man rebelling at a world that is unfair and unjust. Trip's goal isn't simply to help the North defeat the South, but to gain revenge on anyone and everyone who may ever have been responsible for the problems he's had. It's not that Trip is unsympathetic, he may be the most sympathetic character in the entire piece, he just has a very harsh worldview.
As the film progresses, the men learn what Shaw requires of them and Shaw learns how to be a leader. Both end up seeing the world just a little better from the other's perspective. And, essentially, that is what the film is about — it's not just the semi-fictionalized story of the 54th, it's about learning to understand and respect those of a different background.