Years earlier Richard Widmark had the historical subject matter researched at Yale. He brought the material to John Ford, who didn't want to make it. Years later Ford, who had kept the research, changed his mind and asked Widmark to star.
Little Wolf was a chief of the Cheyenne tribe in 1878. He and another chief led the Cheyenne off their Oklahoma reservation and took them back to their homeland in Montana, despite hundreds of US cavalry troops trying to stop them. This was called the "Cheyenne Autumn Trail" and is the basis for this film.
The "Cheyenne" in the film are actually Navajo, and they are speaking in the Navajo language (mostly telling each other dirty jokes).
The final duel between Little Wolf and Red Shirt was shot on the day that President John F. Kennedy was assassinated in Dallas, TX. Though legends say that John Ford, so saddened by the death of the first Irish-descended president of the nation, mourned his death by halting the shoot on that day, production documents actually show that it was the only scene to be shot that day, and they moved from Utah in the afternoon as originally scheduled.