Although Congress abolished slavery in the District of Columbia in 1862, and President Abraham Lincoln’s Emancipation Proclamation ended the practice of slavery in rebellious states in 1863, at war’s end in 1865 the question of slavery had not been resolved at the national level. The federal government required new state constitutions in former Confederate states to include the abolition of slavery, but there was nothing to prevent states from reinstituting the practice with revised state constitutions. Senators Lyman Trumbull of Illinois, Charles Sumner of Massachusetts, and John Henderson of Missouri, sponsored resolutions for a constitutional amendment to abolish slavery nationwide. The Thirteenth Amendment—passed by the Senate on April 8, 1864; by the House on January 31, 1865; and ratified by the states on December 6, 1865—abolished slavery “within the United States, or any place subject to their jurisdiction.” Congress required former Confederate states to ratify the Thirteenth Amendment as a condition of regaining federal representation.
Ratified July 9, 1868, the Fourteenth Amendment granted citizenship to all persons "born or naturalized in the United States," including former enslaved persons, and provided all citizens with “equal protection under the laws,” extending the provisions of the Bill of Rights to the states. The amendment authorized the government to punish states that abridged citizens’ right to vote by proportionally reducing their representation in Congress. It banned those who “engaged in insurrection” against the United States from holding any civil, military, or elected office without the approval of two-thirds of the House and Senate. The amendment prohibited former Confederate states from repaying war debts and compensating former slave owners for the emancipation of their enslaved people. Finally, it granted Congress the power to enforce this amendment, a provision that led to the passage of other landmark legislation in the 20th century, including the Civil Rights Act of 1964, and the Voting Rights Act of 1965. Congress required former Confederate states to ratify the Fourteenth Amendment as a condition of regaining federal representation.
As a member of the Senate Committee on the Judiciary, William Stewart of Nevada guided the Fifteenth Amendment through the Senate. Ratified February 3, 1870, the amendment prohibited states from disenfranchising voters “on account of race, color, or previous condition of servitude.” The amendment left open the possibility, however, that states could institute voter qualifications equally to all races, and many former confederate states took advantage of this provision, instituting poll taxes, and literacy tests, among other qualifications.
The Reconstruction amendments to the Constitution extended new constitutional protections to African Americans, though the struggle to fully achieve equality would continue into the 20th century.