The Emancipation Proclamation

A strict application of the Fugitive Slave Law of 1850 could have required the return of fugitive slaves to their owners. Initially this did not occur because some Union generals declared slaves in reoccupied areas were contraband of war. This was controversial because it could imply some recognition of the Confederacy as a separate nation under international law, a notion that Lincoln steadfastly denied; as a result, he never promoted the contraband designation. Some generals also declared the slaves to be free and were replaced when they refused to rescind such declarations. On March 13, 1862, Lincoln forbade all Union Army officers from returning fugitive slaves. On April 10, 1862, Congress declared that the federal government would compensate slave owners who freed their slaves. All slaves in the District of Columbia were freed in this way on April 16, 1862. On June 19, 1862, Congress prohibited slavery in United States territories, thus opposing the 1857 opinion of the Supreme Court of the United States in the Dred Scott Case that Congress was powerless to regulate slavery in the territories.

In January 1862, Thaddeus Stevens, the Republican leader in the House, called for total war against the rebellion, arguing that emancipation would ruin the rebel economy. In July 1862, Congress passed and Lincoln signed the "Second Confiscation Act." It liberated the slaves held by "rebels". It provided:

“ SEC. 2. And be it further enacted, That if any person shall hereafter incite, set on foot, assist, or engage in any rebellion or insurrection against the authority of the United States, or the laws thereof, or shall give aid or comfort thereto, or shall engage in, or give aid and comfort to, any such existing rebellion or insurrection, and be convicted thereof, such person shall be punished by imprisonment for a period not exceeding ten years, or by a fine not exceeding ten thousand dollars, and by the liberation of all his slaves, if any he have; or by both of said punishments, at the discretion of the court.
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SEC. 9. And be it further enacted, That all slaves of persons who shall hereafter be engaged in rebellion against the government of the United States, or who shall in any way give aid or comfort thereto, escaping from such persons and taking refuge within the lines of the army; and all slaves captured from such persons or deserted by them and coming under the control of the government of the United States; and all slaves of such person found or being within any place occupied by rebel forces and afterwards occupied by the forces of the United States, shall be deemed captives of war, and shall be forever free of their servitude, and not again held as slaves.
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Abolitionists had long been urging Lincoln to free all slaves. A mass rally in Chicago on September 7, 1862, demanded an immediate and universal emancipation of slaves. A delegation headed by William W. Patton met the President at the White House on September 13. Lincoln had declared in peacetime that he had no constitutional authority to free the slaves, but the war gave him war powers. Still, emancipation was a risky political act. Public opinion as a whole was against it. There would be strong opposition among Copperhead Democrats and an uncertain reaction from loyal border states.

Lincoln first discussed the proclamation with his cabinet in July 1862, but he felt that he needed a Union victory on the battlefield so it would not look like an act of desperation. The Battle of Antietam, in which Union troops turned back a Confederate invasion of Maryland, gave him the opportunity to issue a preliminary proclamation on September 22, 1862. The final proclamation was then issued in January of the following year. Although implicitly granted authority by Congress, Lincoln used his powers as Commander-in-Chief of the Army and Navy, "as a necessary war measure" as the basis of the proclamation, rather than the equivalent of a statute enacted by Congress or a constitutional amendment.

The Emancipation Proclamation did not free the slaves; the Thirteenth Amendment did. The Proclamation only gave Lincoln the legal basis in order to free the slaves in the South. Thus, it took effect only as the Union armies advanced into the Confederacy. Slaves in the border states (Delaware, Maryland, Kentucky, Missouri and West Virginia) were emancipated by separate state action. Secretary of State William H. Seward commented on this by remarking, "We show our sympathy with slavery by emancipating slaves where we cannot reach them and holding them in bondage where we can set them free." Had any seceding state rejoined the Union before January 1, 1863, it could have kept slavery, at least temporarily.

The Emancipation Proclamation also allowed for the enrollment of freed slaves into the United States military. Nearly 200,000 blacks did join, most of them ex-slaves. This gave the North an additional manpower resource that the Confederacy would not emulate until the final months before its defeat.