Claim: The Ku Klux Klan flourished in the late 1860s.

The Ku Klux Klan -LRB- KKK -RRB- , or simply the Klan , is the name of three distinct movements in the United States that have advocated extremist reactionary currents such as white supremacy , white nationalism , anti-immigration , and , especially in later iterations , Nordicism , anti-Catholicism , and antisemitism . Historically the KKK used terrorism , both physical assault and murder , against groups or individuals whom they opposed .  All three movements have called for the `` purification '' of American society , and all are considered right-wing extremist organizations .   The first Klan flourished in the Southern United States in the late 1860s , then died out by the early 1870s . It sought to overthrow the Republican state governments in the South during the Reconstruction Era , especially by using violence against African American leaders . With numerous chapters across the South , it was suppressed around 1871 , through federal law enforcement . Members made their own , often colorful , costumes : robes , masks , and conical hats , designed to be terrifying , and to hide their identities .   The second group was founded in 1915 , and it flourished nationwide in the early and mid-1920s , particularly in urban areas of the Midwest and West . It was rooted in local Protestant communities and opposed Catholics and Jews , and stressed its opposition to the Catholic Church at a time of high immigration from mostly Catholic nations of southern and eastern Europe . This second organization adopted a standard white costume and used code words which were similar to those used by the first Klan , while adding cross burnings and mass parades to intimidate others .   The third and current manifestation of the KKK emerged after 1950 , in the form of small , local , unconnected groups that use the KKK name . They have focused on opposition to the Civil Rights Movement , often using violence and murder to suppress activists . It is classified as a hate group by the Anti-Defamation League and the Southern Poverty Law Center . , the Anti-Defamation League puts total Klan membership nationwide at around 3,000 , while the Southern Poverty Law Center -LRB- SPLC -RRB- puts it at 6,000 members total .   The second and third incarnations of the Ku Klux Klan made frequent references to America 's `` Anglo-Saxon '' blood , hearkening back to 19th-century nativism . Although members of the KKK swear to uphold Christian morality , virtually every Christian denomination has officially denounced the KKK .