Films of American frontier life set in periods earlier than the conventional Western moment of the post–Civil War era have sometimes been called pre-Westerns. Pre-Westerns, such as The Last of the Mohicans (1992) and Drums along the Mohawk (1939), exemplify the genre well. The term evidently originated with Philip French (1977).
Historical Dictionary of Westerns in Cinema. Paul Varner. 2012.