The Emancipation Proclamation issued by U.S. President Abraham Lincoln the previous September came into effect on January 1,1863. However it did not abolish slavery. The Proclamation declared free all enslaved people in the Confederate States who resided in territory still in rebellion against the United States. As the Union Army captured more Confederate territory it would also liberate enslaved people living in that territory. Emancipation and abolition of slavery only became law in the U.S. through the 13th Amendment to the Constitution after it was ratified by 2/3 of the states on December 6, 1865.