Frank M. Canton (born Josiah Horner, 1849–1927) was an American Old West figure who reinvented himself from a fugitive bank robber and cattle rustler into a deputy U.S. marshal under an assumed name. As a stock detective for Wyoming's powerful cattle barons, he was accused of using assassination and extrajudicial violence, including the lynching of Ellen Watson, to suppress small ranchers. In 1892, he directed the infamous Johnson County War, leading a vigilante force of imported gunmen to the KC Ranch, where they killed Nate Champion and Nick Ray, though the siege ended only when the U.S. Cavalry rescued them from a local posse. After being freed and facing a lynch mob himself, Canton left Wyoming and spent the rest of his career in law enforcement under the notorious "hanging judge" Isaac C. Parker. He died in 1927, leaving a legacy as a controversial figure who blurred the line between lawman and outlaw.