Little Big Man, 1970.
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The role of Old Lodge Skins was initially offered to Marlon Brando, who turned it down. Other sources claim Arthur Penn's first choice for the role was Sir Laurence Olivier. When that didn't work out, Richard Boone was slated for the role. When Boone backed out at the last minute, Chief Dan George was given the part and earned an Oscar nomination.
Little Big Man was the name of an actual historical figure. He was a Native American, an Oglala Lakota, who was a fearless and respected warrior who fought under, and was rivals with, Crazy Horse. He also fought at the Battle of Little Big Horn, a battle which is depicted in this film.

