In Earth's Ancient West, the Clanton gang were criminals who engaged in the famous Battle at the OK Corral in 1881 against the rival Earp gang. (TOS: "Spectre of the Gun" ) In Chicago of the 1920s, when members of criminal organizations were sometimes referred to as gangsters, gangs almost took over from conventional government when the latter nearly broke down. One book that was published about the gang culture of that time was Chicago Mobs of the Twenties. (TOS: "A Piece of the Action" ) A similar gang-related publication was Chicago Gangs. (ENT: "Horizon")