Frontier Marshal is a 1934 American Pre-Code Western film directed by Lewis Seiler and starring George O'Brien. Produced by Fox Film and Sol M. Wurtzel, the film is the first based on Stuart N. Lake's enormously popular but largely fictitious "biography" of Wyatt Earp, Wyatt Earp: Frontier Marshal. A second version of the film, also produced by Wurtzel, was made in 1939, and a third interpretation by John Ford entitled My Darling Clementine was released in 1946.