In high school we were taught that Abraham Lincoln freed the slaves. His Emancipation Proclamation reads in part "On the 1st day of January, A.D. 1863, all persons held as slaves within any State or designated part of a State the people whereof shall then be in rebellion against the United States shall be then, thenceforward, and forever free" (http://www.thecre.com/fedlaw/legal9/emancipation.htm).
But a closer inspection of the document reveals that Lincoln's action provided nothing close to a blanket freedom for slaves. It freed only slaves in rebel territory, but specifically did not free them in the border states on the Union side, nor in the southern states wrested from Confederate control. As Secretary of State William Seward wryly observed, "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" (http://en.wikipedia.org/wiki/Emancipation_Proclamation).
Part of the reason for the Proclamation was the benefit of the significant increase in manpower that freed blacks would provide for the Union army, albeit under conditions of complete racial segregation. Although numerous slaves volunteered to fight for the North in return for their freedom at the beginning of the Civil War, slaves captured from Confederate forces in the South were at first interred in camps. But on March 13, 1862 the federal government forbade their return to their owners as Fugitive Slave Law of 1850 required, thus overturning it.
An estimated 200,000 black men joined the Union army subsequent to the Proclamation, providing the North with an important military advantage. In the meantime, the slaves who had been the backbone of Confederate war production and logistical support were given an added incentive to try to escape to the North, further eroding Southern morale and manpower.
Northern white abolitionist politicians hailed Lincoln's policy,
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