Custer's storied defeat at the hands of the Lakota Souix out in the Dakotas.
We do love our epics of defeat here in the West, from Thermopylae to Waterloo down thru the Seventh Cavalry's sabres glittering in the sun on the bluffs above the Little Big Horn.
Custer has had strong popularity in multimedia as well...from Thomas Ince's 1912 film "The Death of Custer" down to "Little Big Man".
The weirdest film incarnation of the boy general is still under the tutelage of dependable Hollywood hack Sidney Salkow who directed not one but two "pro Indian" westerns about the Little Big Horn. "Sitting Bull" (1956) with J. Carroll Naish in redface as the mighty medicine man and "The Great Souix Massacre" (1965) featured red haired Darren "Kolchak the Night Stalker" McGavin as the only honest man in Custer's command. Both were about as historically accurate as a Ned Buntline dime novel and both suffered from an excess of naivete' about the position of Native Americans in the modern USA.
But what the hell, they are an attempt to break with past proactice no matter how silly or bumptious they may be.