among the states. The Fugitive Slave Clause (Article IV, Section 2, Clause 3) provided that slaves held under the laws of one state who escaped to another state did not become free, but remained slaves.

Though three million Confederate slaves were eventually freed as a result of Lincoln's Emancipation Proclamation, their postwar status was uncertain. To ensure that abolition was beyond legal challenge, an amendment to the Constitution to that effect was drafted. On April 8, 1864, the Senate