The Emancipation Proclamation affected the Union’s Civil War efforts by

The Emancipation Proclamation declared enslaved people in areas rebelling against the Union to be free, and it also opened the way for African American men to enlist in the Union Army. Their service increased the number of troops available to the Union. It did not force all Southern slaveholders to free enslaved people immediately, nor did it require Northern African Americans to join the army.

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