I remember seeing a film in college on the black unit in WWI. They started out unloading ships for the AEF, and when they were finally allowed to go to the front, they were given to the French instead of fighting with American units. The French didn't care about what color they were since they desparately needed fresh troops and they had used colonial troops from Africa since 1914. As I recall, the unit served well for the French, and was the only Allied unit to reach German soil before the armistice. They also had one of the best bands in any army since they were from Harlem and and had many Jazz musicians in their ranks.
Plus they didn't have that pesky French habit of saying "I surrender" in response to any question. ;-)