Final answer:
The issuance of the Emancipation Proclamation turned the Civil War in the North's favor.
Step-by-step explanation:
The Civil War, war effort, turned decidedly in the North's favor following the issuance of the Emancipation Proclamation. This executive order, issued by President Abraham Lincoln, declared that all enslaved individuals in Confederate territory were to be set free. It not only changed the objective of the war from preserving the Union to ending slavery, but also provided a moral and political justification for the North's cause. The Emancipation Proclamation boosted morale and support for the Union in the North and garnered international sympathy, ultimately shifting the momentum of the war in their favor.
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