Yes I know what the modern common preception of the KKK is. But in the 5 years following the war when the ORIGINAL KKK was formed were lawless times. No one had clean heands from the corruption and thuggery. Remember Ashley and Mr. Kennedy in "Gone with the Wind" and the attack on Scarlet in the Contriband Camp?
That may be romanticised, but what was it based on? Did the Klan degenerate and become co opted? Yes, that is why it was disbanded in 1870.