Adventurers swarmed out of the North, as much the enemies of one race as of the other, to cozen, beguile and use the negroes. The white men were aroused by a mere instinct of self-preservation — until at last there sprung into existence a great Kuklux Klan, a veritable empire of the South, to protect the Southern country.

A History of the American People (1901), describing the Klan as a brotherhood of politically disenfranchised white men; famously quoted in The Birth of a Nation (1915).