Video: 'Lincoln Signs the Emancipation Proclamation | Abraham Lincoln'

(Thursday, January 1, shortly after noon; during the American Civil War and Slavery in the United States) — U.S. President Abraham Lincoln today signed the final Emancipation Proclamation, which changed the legal status of more than 3.5 million enslaved African Americans in the secessionist Confederate states from enslaved to free.

Video: 'History in Five: Abraham Lincoln and the Emancipation Proclamation'

As soon as slaves escaped the control of their enslavers, either by fleeing to Union lines or through the advance of federal troops, they were permanently free.

Video: 'Lincoln PBS 1992 - Part 2' (Jan. 1, 1863, at 16:08)

In addition, the Proclamation allowed for former slaves to “be received into the armed service of the United States.”

Video: 'The Emancipation Proclamation'

A preliminary proclamation had been issued in September 1862, following the Union victory at the Battle of Antietam in Maryland.

Video: 'Emancipation Proclamation -- Hear and Read the Full Text -- Abraham Lincoln'

The act signaled an important shift in the Union’s Civil War aims, expanding the goal of the war from reunification to include the eradication of slavery.