What amendment to the US Constitution abolished slavery?

The Thirteenth Amendment to the United States Constitution stands as a monumental declaration, formally abolishing slavery and involuntary servitude across the nation. Ratified on December 6, 1865, it was a pivotal moment following the American Civil War, solidifying the end of a system that had deeply divided the country since its inception (Review). While President Abraham Lincoln's Emancipation Proclamation in 1863 had declared enslaved people in Confederate states to be free, it was a wartime measure and did not universally end slavery. The Thirteenth Amendment provided the permanent legal framework for nationwide abolition, ensuring that the institution of chattel slavery could not return.

Before this amendment, the U.S. Constitution only indirectly acknowledged slavery through clauses like the Three-fifths Compromise, which counted enslaved individuals as three-fifths of a person for representation, and the Fugitive Slave Clause, which required the return of escaped enslaved people. The widespread practice of slavery, particularly in the Southern states, fueled intense political debate and ultimately led to the Civil War. The Thirteenth Amendment, therefore, was not merely an act of legislation but the culmination of decades of abolitionist efforts and the immense sacrifices made during the war, providing a "constitutional guarantee" of freedom.

Beyond simply ending chattel slavery, the Thirteenth Amendment also broadly prohibits "involuntary servitude," except as punishment for a crime. This provision has historically been used to strike down other forms of forced labor, such as peonage, and continues to be relevant in addressing modern forms of exploitation like human trafficking. As the first of the three Reconstruction Amendments, it laid the groundwork for further constitutional changes aimed at establishing civil rights for formerly enslaved people, fundamentally reshaping the legal and social landscape of the United States.