Thirteenth amendment

The Thirteenth Amendment to the U.S. Constitution officially abolished and continues to prohibit slavery and involuntary servitude, except as punishment for a crime. It was adopted on December 6, 1865, and was then declared in a proclamation of Secretary of State William H. Seward on December 18, 1865.

President Abraham Lincoln and others were concerned that the Emancipation Proclamation would be seen as a temporary war measure and so, besides freeing slaves in those states where slavery was still legal, they supported the amendment as a means to guarantee the permanent abolition of slavery.