The Freedom Riders were civil rights activists who rode interstate buses in the early 1960s to challenge segregation in the southern United States. They aimed to test the enforcement of the Supreme Court's ruling in Boynton v. Virginia, which declared segregation in public transportation illegal. These riders faced violent opposition and arrests, particularly in states like Alabama and Mississippi. Their courageous actions drew national attention to the civil rights movement and helped lead to the eventual desegregation of public transportation across the country.