"Today, most citizens register to vote without regard to race or color by signing their name and address on something like a postcard. But it was not always so.
Prior to passage of the federal Voting Rights Act in 1965, Southern (and some Western) states maintained elaborate voter registration procedures whose primary purpose was to deny the vote to nonwhites. This process was often referred to as a "literacy test." But in fact, it was much more than just a reading test, it was an entire complex system devoted to denying African-Americans (and in some regions, Latinos and Native Americans) the right to vote.
The registration procedures, and the Registrars who enforced them, were but one part of an interlocking system of racial discrimination and oppression. The various state, county, and local police forces — all white of course — routinely intimidated and harassed Blacks who tried to register.
Via Seth Dixon