In 1925 an all-black baseball team in Wichita, Kansas played an exhibition against a local KKK Klavern, with Irish Catholics serving as umpires. The black team won 10-8.
Stetson Kennedy infiltrated the KKK, learned their rituals and codewords, and provided these to the writers of the Superman program, which produced 16 episodes in which Superman fought the Klan, leading to a steep drop in recruitment.
A KKK Grand Dragon, confined to a wheelchair, had been threatening a local rabbi. The rabbi responded by offering the man compassion, friendship, and transportation around town. They became friends and the Grand Dragon eventually quit the KKK and converted to Judaism.
The FBI recruited a Mafia enforcer to use “illegal interrogation techniques” on KKK members to find the bodies of three missing civil rights workers. It worked.
In 1957, the KKK planned to set up a burning cross at a college in Alabama that recently integrated. However, because it was finals week, the students were all in their dorms and heard the KKK outside. The students then attacked the KKK with bats and golf clubs and forced them to retreat.
In 1958, The Lumbee Indians of North Carolina learned of a KKK rally being held in the woods nearby. They attacked the KKK rally and broke it up. The Klan was never active in the area again. During the ensuing madness the Klan leaders wife drove into a ditch… and then some Lumbee men helped pull her out and sent her on her way.
Walter White, a light-skinned black man, disguised himself as a white man to investigate the KKK.