Which U.S. constitutional amendment abolished slavery after the Civil War?

The Thirteenth Amendment abolished slavery in the United States after the Civil War.

Congress passed the amendment on January 31, 1865, and the required number of states ratified it on December 6, 1865. It outlawed slavery and involuntary servitude throughout the country, except as punishment for a crime after conviction. The amendment therefore ended the legal institution of slavery rather than merely limiting it in particular territories.

The Emancipation Proclamation, issued by President Abraham Lincoln in 1863, had declared enslaved people in rebelling areas to be free. It did not itself abolish slavery everywhere, however. The Thirteenth Amendment provided the nationwide constitutional prohibition and also gave Congress power to enforce it through legislation.

The amendment was the first of the three Reconstruction Amendments. The Fourteenth Amendment addressed citizenship and equal protection, while the Fifteenth Amendment prohibited denying men the vote based on race. Together, these amendments reshaped the constitutional order after the Civil War.