Imagine a political movement created in a moment of terrible anxiety, its origins shrouded in a peculiar combination of manipulation and grass-roots mobilization, its ranks dominated by Christian conservatives and self-proclaimed patriots, its agenda driven by its members’ fervent embrace of nationalism, nativism and moral regeneration, with more than a whiff of racism wafting through it.
The Invisible Empire of the Knights of the Ku Klux Klan, they called it. And for a few years it burned across the nation, a fearsome thing to behold. In “One Hundred Percent American,” Thomas R. Pegram, a professor of history at Loyola University Maryland, traces the Invisible Empire’s meteoric rise and equally precipitous fall. The ’20s Klan was born, he explains — or more precisely was reborn — on Thanksgiving evening 1915, when 16 Southerners trooped up Stone Mountain, in Georgia, for a bit of ritual bunkum inspired by D. W. Griffith’s incendiary film “The Birth of a Nation.”