On January 1, 1863, President Abraham Lincoln put his signature on the Emancipation Proclamation. Many people believe that the Proclamation was a law abolishing slavery, but in fact it was not.
The Proclamation was actually just an executive order that proclaimed the freedom of the slaves in the remaining 10 Confederate states. It did not outlaw slavery or make the freed slaves citizens, although it did allow them to join the Union Army.
It is estimated that only 20,000 to 50,000 slaves (those in areas where the rebellion had already been subdued) were freed immediately, as the Proclamation was unenforceable in the remaining Confederate states. It took a number of years before the last of the estimated 4 million slaves were freed.
Click on the image of the full Proclamation below to view the full size version.