Unforgivable Blackness: The Rise and Fall of Jack Johnson was made by Ken Burns for PBS in 2005. I watched it when it first came out and rewatched it yesterday. It's an amazing story and the production value of the film is top notch.
Background for anyone unfamiliar with Jack Johnson-
In the early 1900s, the three main sports in America were baseball, horse racing, and boxing. Jack Johnson taunted the heavyweight champion into fighting him, won, and became the first minority celebrity in American history. Boxing fans then went looking for the "great white hope" to take the belt back.
The best story about Johnson, which I can't believe is true but I hope it is, is that in 1915 he was flying down a street in his sports car. A cop pulled him over and informed him that it would be a $50 fine (a large sum in 1915). Jack Johnson supposedly handed him a hundred dollar bill and told the cop that he would be coming back this way too.
https://www.youtube.com/watch?v=UH8jA2nm5Vo