The disintegration of slavery was one among several considerations that led President Lincoln, on January 1, 1863, to issue the Emancipation Proclamation.

Lack of military success, pressure from antislavery Northerners, the need to forestall British recognition of the Confederacy, and the desire to tap Southern black manpower for the Union army also contributed to the decision.

The Proclamation, which applied only to areas outside Union control, did not immediately abolish slavery. But it made emancipation an irrevocable war aim, profoundly changing the character of the Civil War.