US secret society dedicated to white supremacy, founded 1866 in the southern states of the USA to oppose Reconstruction after the Civil War and to deny political rights to the black population. Members wore hooded white robes to hide their identity, and burned crosses as a rite of intimidation. It was as active in the 1960s in terrorizing civil-rights activists and organizing racist demonstrations. Its violence led the government to pass the restrictive Ku Klux Klan Acts of 1871. The society re-emerged in 1915 in Atlanta, Georgia, and increased in strength during the 1920s as a racist, anti-Semitic, anti-Catholic, and anti-Communist organization.