This is a list of Old West gunfighters, referring to outlaws or lawmen, of the American frontier who gained fame or notoriety during the American Wild West or Old West. The term gunslinger is a modern, 20th century invention, often used in cinema or other media to refer to men in the American Old West who had gained a reputation as being dangerous with a gun. A gunfighter may or may not be an outlaw or a lawman. An outlaw had usually been convicted of a crime such as Black Bart, but may have only gained a reputation as operating outside the law such as Ike Clanton. Some of those listed may have also served in law enforcement like Marshal Burt Alvord who subsequently became an outlaw, and some outlaws like Johnny Ringo were deputized at one time or another. Some of the gunfighters listed included professional scouts, businessmen, or even doctors.
The majority of outlaws in the Old West preyed on banks, trains, and stagecoaches. Some crimes were carried out by Mexicans and Native Americans against white citizens who were targets of opportunity along the U.S.–Mexico border, particularly in Texas, New Mexico, Arizona, and California. For example Pancho Villa was a bandit from Durango, Mexico who also conducted cross-border raids into New Mexico and Texas. Some individuals, like Jesse James, Bob Stage became outlaws after serving in the Civil War and others were simply men who took advantage of the wildness and lawlessness of the frontier to enrich themselves at the expense of others. Some outlaws migrated to the frontier to escape prosecution for crimes elsewhere.
Law was present if spread thin in the American Old West. It was usually present on three levels: the Deputy U.S. Marshal, the county sheriff, and the town marshal or constable. Sometimes their jurisdictions overlapped which could lead to conflicts like those between Deputy U.S. Marshal Virgil Earp and Cochise County, Arizona Sheriff Johnny Behan. When an outlaw committed a crime, the local sheriff or marshal would usually form a posse to attempt to capture them. Rewards were posted for outlaws which encouraged citizens to capture or kill them for the reward, leading to the profession of bounty hunter.