An extremist, paramilitary, right-wing secret society founded in the mid-nineteenth century and revived during the 1920s. It was anti-foreign, anti-black, anti-Jewish, anti-pacifist, anti-Communist, anti-internationalist, anti-evolutionist, and anti-bootlegger, but pro-Anglo-Saxon and pro-Protestant. Its members, cloaked in sheets to conceal their identities, terrorized freedmen and sympathetic whites throughout the South after the Civil War.