On December 24, 1865, a group of former Confederate soldiers established what would become the first chapter of the Ku Klux Klan, or KKK, in Pulaski, Tennessee. Named for the Greek word “kyklos,” which means circle, the KKK was devoted to white supremacy and to ending Reconstruction in the South. The Klan’s first leader, called a Grand Wizard, was former Confederate Lieutenant General Nathan Bedford Forrest.

During Reconstruction, the KKK's political activity was closely tied to the goals of Southern politicians still loyal to the cause of white supremacy. To support this agenda, the Klan engaged in a campaign of terror, violence, and murder, targeting African Americans as well as white voters who supported racial equality and civil rights. Writing in 1935, scholar W.E.B. DuBois described Klan attacks as “armed guerilla warfare” and estimated that, between 1866 and mid-1867, the KKK was responsible for 197 murders and 548 aggravated assaults in North and South Carolina alone. Reconstruction-era KKK terror went largely unopposed by local authorities, spurring federal intervention. In 1871, the U.S. Congress passed the Force Bill, which allowed for prosecution of Klan members in federal court and dramatically slowed Klan activity; by the early 1870s, the Klan had all but disappeared.

The KKK underwent a massive resurgence in the first few decades of the 20th century, due in large part to the film Birth of a Nation, which glorified the group’s 19th-century activities. In the first half of the 20th century, Klan membership became a core qualification for public office in Southern states. Many influential national figures were Klansmen at some point in their lives, including Senator Robert Byrd (D-WV) and former U.S. Supreme Court Justice Hugo Black. The Klan persists today but is estimated to have only about 3,000 active members, down from a high of more than 2,000,000 members in the 1920s.