The Ku Klux Klan (ˌkuː_klʌks_ˈklæn,_ˌkjuː-), commonly shortened to the KKK or the Klan is the name of several historical and current American white supremacist, far right-wing terrorist, and hate groups. Their primary targets are African Americans, Hispanics, Jews, Latinos, Asian Americans, Native Americans, and Catholics, as well as immigrants, leftists, homosexuals, Muslims, atheists, and abortion providers.
Three separate Klans have existed in three non-overlapping time periods. Each comprised local chapters with little or no central direction. Each has advocated extremist reactionary positions such as white nationalism, anti-immigration and—especially in later iterations—Nordicism, antisemitism, anti-Catholicism, Prohibition, right-wing populism, anti-communism, homophobia, anti-atheism, and Islamophobia. The first Klan founded by Confederate veterans used terrorism—both physical assault and murder—against politically active Black people and their allies in the Southern United States in the late 1860s. The second iteration of the Klan originated in the late 1910s, and was the first to use cross burnings and hooded robes. The KKK of the 1920s had a nationwide membership in the millions and reflected a cross-section of the native-born white population. The third Klan formed in the mid 20th century, largely as a reaction to the growing civil rights movement. It committed murders and bombings to achieve its aims. All three movements have called for the "purification" of American society, and are all considered far-right extremist organizations. In each era, membership was secret and estimates of the total were highly exaggerated by both friends and enemies.
The first Klan was established in the wake of the American Civil War and was a defining organization of the Reconstruction era. Organized in numerous independent chapters across the Southern United States, federal law enforcement suppressed it around 1871. It sought to overthrow the Republican state governments in the South, especially by using voter intimidation and targeted violence against African-American leaders.