Little Big Man (1970)

When a curious oral historian (William Hickey) turns up to hear the life story of 121-year-old Jack Crabb (Dustin Hoffman), he can scarcely believe his ears. Crabb tells of having been rescued and raised by the Cheyenne, of working as a snake-oil salesman, as a gunslinger, and as a mule skinner under Gen. Custer (Richard Mulligan). As if those weren't astonishing enough, he also claims to be the only white survivor of the infamous Battle of the Little Bighorn.