The Ku Klux Klan (KKK, the Klan), founded in 1865 in Pulaski, Tennessee, was established as a direct response to the South's defeat in the Civil War. As a secret vigilante group, the Klan targeted black freedmen and their allies; it sought to restore white supremacy by threats and violence, including beatings, lynchings, and murder. Blacks lived in fear of groups like the Klan who exerted reign of terror across the South where their crimes were rarely prosecuted.
In the 1870s, the U.S. Congress took action to curtail the violence and the organization by using Enforcement Acts to prosecute Klansmen. The Klan experienced a resurgence in 1915 with the release of the W.D. Griffith's film "Birth of a Nation" and the murder trial and subsequent lynching of Jewish-American factory owner Leo M. Frank. Revived near Atlanta, Georgia, the new KKK's rapid growth was based not only on the idea of white supremacy, but also on anti-immigration, anti-Catholicism, Prohibition, and anti-Semitism. The KKK reached its peak nationwide in the 1920s.
After WWII, the name Ku Klux Klan was used by numerous groups throughout the South who opposed the civil rights movement and desegregation. These groups used cross burnings, beatings, bombings, and murder to intimidate civil rights activists and local black communities. During this period, the groups often forged alliances with police departments and state offices to further their cause. The U.S. government revived the Force Acts in 1963, when Mississippi officials refused to prosecute KKK members for the murder of three civil rights workers, James Earl Chaney, Andrew Goodman, and Michael Schwerner.
During the late 1960s and 1970s, the KKK shifted its focus to one opposing affirmative action, immigration, and court-ordered school busing. In 1971, KKK members blew up school buses in Pontiac, Michigan in an attempt to stop a court-ordered school desegregation plan. Today, researchers estimate that there are as many as 150 Klan chapters active in the U.S. with between 5,000 and 8,000 members nationwide.