Emancipation Proclamation.
Initially, the Civil War between the North and the South was fought by the North to prevent the secession of the South and preserve the Union. Ending slavery was not a goal. That changed on September 22, 1862, when President Abraham Lincoln issued his Preliminary Emancipation Proclamation, which stated that slaves in those states or parts of states still in rebellion as of January 1, 1863, would be free. One hundred days later Lincoln issued the Emancipation Proclamation declaring "that all persons held as slaves" within the rebellious areas "are, and henceforward shall be, free." Lincoln's bold step was a military measure by which he hoped to inspire the slaves in the Confederacy to support the Union cause. Because it was a military measure, the proclamation was limited in many ways. It applied only to states that had seceded from the Union, and left slavery untouched in the border states. Although the Emancipation Proclamation did not end slavery, it did fundamentally transform the character of the war. Henceforth, every advance of Federal troops expanded the domain of freedom. Moreover, the proclamation announced the acceptance of black men into the Union Army and Navy. By the end of the war, almost 200,000 black soldiers and sailors had fought for the Union and their own freedom.