The first Klan was founded in 1865 by Tennessee veterans of the Confederate Army. Klan groups spread throughout the South. The Klan's purpose was to restore white supremacy in the aftermath of the American Civil War. The Klan resisted Reconstruction by assaulting, murdering and intimidating freedmen and white Republicans. In 1870 and 1871 the federal government passed the Force Acts, which were used to prosecute Klan crimes. Prosecution of Klan crimes and enforcement of the Force Acts suppressed Klan activity. In 1874 and later, however, newly organized and openly active paramilitary organizations such as the White League and the Red Shirts started a fresh round of violence aimed at suppressing Republican voting and running Republicans out of office. These contributed to white Democrats regaining political power in the Southern states in the late 19th and early 20th centuries.
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Historian Elaine Frantz Parsons commented on the make up of the membership:
Lifting the Klan mask revealed a chaotic multitude of antiblack vigilante groups, disgruntled poor white farmers, wartime guerrilla bands, displaced Democratic politicians, illegal whiskey distillers, coercive moral reformers, sadists, rapists, white workmen fearful of black competition, employers trying to enforce labor discipline, common thieves, neighbors with decades-old grudges, and even a few freedmen and white Republicans who allied with Democratic whites or had criminal agendas of their own. Indeed, all they had in common, besides being overwhelmingly white, southern, and Democratic, was that they called themselves, or were called, Klansmen
Historian Eric Foner observed:
In effect, the Klan was a military force serving the interests of the Democratic party, the planter class, and all those who desired restoration of white supremacy. Its purposes were political, but political in the broadest sense, for it sought to affect power relations, both public and private, throughout Southern society. It aimed to reverse the interlocking changes sweeping over the South during Reconstruction: to destroy the Republican party's infrastructure, undermine the Reconstruction state, reestablish control of the black labor force, and restore racial subordination in every aspect of Southern life.[24]
To that end they worked to curb the education, economic advancement, voting rights, and right to keep and bear arms of blacks.[24] The Ku Klux Klan soon spread into nearly every southern state, launching a "reign of terror" against Republican leaders both black and white. Those political leaders assassinated during the campaign included Arkansas Congressman James M. Hinds, three members of the South Carolina legislature, and several men who served in constitutional conventions."[25]