Which group was known for using violence to restore white authority in the post-Civil War South?

The group known for using violence to restore white authority in the post-Civil War South is the Ku Klux Klan. Following the Civil War, during the Reconstruction era, the Klan emerged as a domestic terrorist organization aimed at undermining the social, economic, and political advancements of African Americans. They employed intimidation, violence, and murder against Black individuals and their allies in order to re-establish white supremacy and resist Reconstruction policies.

The Klan’s activities were marked by lynchings, beatings, and other forms of brutal enforcement of racial hierarchy, which instilled fear in the Black community and aimed to deter them from exercising their newfound rights, including voting and holding public office. This context highlights the Klan's role as a significant force in the backlash against the progress made during Reconstruction, making them synonymous with the violent restoration of white authority during that period.

The other groups mentioned have distinct purposes and contexts that do not align with the violent restoration of white supremacy. The Freedom Riders were civil rights activists who rode interstate buses into the Southern United States to challenge segregation. The Black Panthers were a revolutionary socialist organization focused on self-defense and community empowerment for Black Americans in the mid-20th century, while the NAACP is a civil