President Lincoln issued the Emancipation Proclamation after

The Union victory at Antietam in September 1862 gave President Lincoln the military success he needed to announce the Emancipation Proclamation without making it appear to be a desperate move. He issued the preliminary proclamation shortly afterward, declaring that enslaved people in areas still rebelling would be freed beginning January 1, 1863. Antietam was a Union victory, not a loss for General McClellan, and Lee did not capture Washington, DC.

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