15th Amendment to the United States Constitution

The Fifteenth Amendment (Amendment XV) to the United States Constitution prohibits the federal and state governments from denying a citizen the right to vote based on that citizen's "race, color, or previous condition of servitude". It was ratified on February 3, 1870, as the third and last of the Reconstruction Amendments.

In the final years of the American Civil War and the Reconstruction Era that followed, Congress repeatedly debated the rights of the millions of black former slaves. By 1869, amendments had been passed to abolish slavery and provide citizenship and equal protection under the laws, but the election of Ulysses S. Grant to the presidency in 1868 convinced a majority of Republicans that protecting the franchise of black male voters was important for the party's future. On February 26, 1869, after rejecting more sweeping versions of a suffrage amendment, Congress proposed a compromise amendment banning franchise restrictions on the basis of race, color, or previous servitude. After surviving a difficult ratification fight, the amendment was certified as duly ratified and part of the Constitution on March 30, 1870.

United States Supreme Court decisions in the late nineteenth century interpreted the amendment narrowly. From 1890 to 1910, most black voters in the South were effectively disenfranchised by new state constitutions and state laws incorporating such obstacles as poll taxes and discriminatory literacy tests, from which white male voters were exempted by grandfather clauses. A system of whites-only primaries and violent intimidation by white groups also suppressed black participation.

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