1918 - Harlem Hellfighters never recognized for their bravery (watch)
The Harlem Hellfighters were an African-American infantry unit in WWI who spent more time in combat than any other American unit. Despite their courage, sacrifice and dedication to their country, they returned home to face racism and segregation from their fellow countrymen.
Watch: http://www.history.com/topics/world-war-i/world-war-i-history/videos/the-harlem-hellfighters