The film was originally denied a seal from the Production Code Administration. Geoffrey Shurlock told producer Howard W. Koch that it contained "sadism and excessive gruesomeness". To get a seal, Koch reduced the number of killings from 24 to 10. Removed were scenes where a man is spread-eagled and torn apart by horses; an arrow impaling a hand to wood; and a scene depicting the bodies of hanged Indians, swaying from tree limbs.
Despite what another Trivia entry claims, the number of on-screen killings in the film was not reduced to 10 for censorship reasons. In fact, there are over 30 on-screen killings during the course of the film, of whites and Indians.
Capt. Santley sending a message to the General orders Pvt. Cassidy to "step on it". This phrase, to go fast, came from foot pedals in automobiles and pressing down to go faster. It would not have been a phrase used in the wild west.