The Selma and Montgomery marches were part of a broader voting rights movement throughout American letters.
 From 1888 to 1908, Southern states legalized disenfranchisement by enacting Jim Crow laws; they amended their constitutions and passed legislation to impose various voting restrictions, including literacy tests, poll taxes, property-ownership requirements, moral character tests, requirements that voter registration applicants interpret particular documents, and grandfather clauses that allowed otherwise-ineligible persons to vote if their grandfathers voted (which excluded many African Americans whose grandfathers had been slaves or otherwise ineligible)
 After Johnson signed the Act into law, newly enfranchised racial minorities began to vote for liberal Democratic candidates throughout the South, and Southern white conservatives began to switch their party registration from Democrat to Republican en masse

