Grandfather clauses were attached to literacy test and poll tax laws in the south in order to disenfranchise African-American voters. The clauses exempted anyone whose ancestors had voted before the Civil War from taking the literacy test and paying the poll tax, which effectively excluded many African Americans from voting because their ancestors had been slaves and were not allowed to vote. These clauses were a part of a broader systemic effort to prevent African Americans from exercising their right to vote and participating in the political process, which is commonly referred to as voter suppression.