The Hillboys was the nickname given to a loose alliance of local guerrilla units in the Confederate States of America that fought the United States occupation of the Confederacy, with some (e.g. Arizona Brigade of Citizens) starting their campaigns as early as 1913. The Hillboys were distinct from the Sons of the South and Last Defense Regiment in that their membership was mostly exclusively from areas under direct occupation, and unlike the Ku Klux Klan, which also relied upon anonymity, did not have rituals or formal titles and exclusively fought occupying forces and locals thought sympathetic to the American occupiers, as opposed to attacking blacks, Jews and Catholics as well.
The most successful Hillboy regiment was arguably the Arizona Brigade of Citizens (ABC), whose leaders evaded capture and were soon conducting campaigns not only in Arizona and New Mexico but in the US States of California, Nevada and Utah as well as in parts of northern Mexico, where they fought alongside Mexican rebels. Other prominent groups include the Oklahoma Hillboys, who were notable for their inclusion of Native Americans within their ranks; the Kentucky Hillboys, who were the most numerically vast group; and the Virginia Hillboys, who were infamous for the Lynchburg Affair, one of the most brutal acts of violence of the entire occupation. Historians often compare the Hillboys to Minutemen from the American Revolutionary War.