Contrary to popular belief, no clips from this movie were used in the flashback scenes in John Wayne's final movie, The Shootist (1976).
The passage Randy reads from Quirt's Bible is from either 2 Samuel 23:20-1 or 1 Chronicles 11:22-3.
It was the first film produced by John Wayne's production company, and it was also Wayne's first producing effort for Republic.
A quirt is a short whip with a braided leather tail that is used by cowboys to move cattle while being herded.
The failure of the original copyright holder to renew the film's copyright resulted in it falling into public domain, meaning that virtually anyone could duplicate and sell a VHS/DVD copy of the film. Therefore, many of the versions of this film available on the market are either severely (and usually badly) edited and/or of extremely poor quality, having been duped from second- or third-generation (or more) copies of the film.