The right to vote was first guaranteed to black Americans (or at least black males) in 1870 with the passage of the 15th Amendment; but for nearly 100 years after, that right was systematically obstructed in many places across the nation. (Even now, voting rights remain contentious with portions of the Voting Rights Act of 1965 having been struck down by the Supreme Court in 2013 and new voter ID laws sparking heated debate over the impact on voter participation).
By the early 1960s, things were particularly bad in portions of the South – especially in Alabama, which had become a flashpoint for civil rights battles since Rosa Parks refused to give up her seat on a segregated bus in Montgomery. Throughout the state, black citizens applying to vote were repeatedly blocked by local registrars – known to give impromptu literacy and civics tests featuring absurdly difficult questions designed to fail all takers. Furthermore, widespread poll taxes discouraged the poor and penalized those who chose to vote even if they succeeded in getting registered. By 1965, there were counties in Alabama where not a single black person had voted in any election for the previous 50 years.