Before he could issue the Emancipation Proclamation, President Lincoln waited for

Lincoln waited for a Union military success before announcing the preliminary Emancipation Proclamation. He wanted to issue it from a position of strength rather than have it appear to be a desperate response to battlefield setbacks. The Union victory at Antietam in September 1862 gave him the opportunity to announce it; the proclamation took effect on January 1, 1863.

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