The Emancipation Proclamation consists of two executive orders issued by United States President Abraham Lincoln during the American Civil War. The first one, issued on September 22, 1862, declared the freedom of all slaves in any state of the Confederate States of America as did not return to Union control by January 1, 1863, and the second one, issued on January 1, 1863, enumerated the specific states where it applied.
The Emancipation Proclamation was widely attacked at the time as freeing only the slaves over which the Union had no power, but in practice, it committed the Union to ending slavery, which was controversial in the North. It was not a law passed by Congress, but a presidential order empowered, as Lincoln wrote, by his position as "Commander in Chief of the Army and Navy" under Article II, section 2 of the United States Constitution.
The proclamation did not free any slaves in the border states (Kentucky, Missouri, Maryland, Delaware, and West Virginia), or any southern state already under Union control. It first directly affected only those slaves that had already escaped to the Union side, but as the Union armies conquered the Confederacy, thousands of slaves were freed each day until nearly all (an estimated 4 million) were freed by July of 1865.