At first, President Lincoln argued that freeing enslaved people was not the primary goal of the war—preserving the Union was. But tens of thousands of enslaved people freed themselves as soon as they could by making their way to the Union side. Among the first to do so were three men—Shepard Mallory, Frank Baker, and James Townsend—who rowed a boat across the harbor near Hampton, Virginia, in May 1861 and sought the protection of Union forces. Thereafter, enslaved people rushed to gain freedom behind Union lines.

Lincoln came to realize that slavery had to be abolished to ensure a Union victory. The millions of enslaved people working on plantations enabled the South to put nearly all of its able-bodied white men on the battlefield. Antislavery leaders like Frederick Douglass, a noted black writer, also argued that the war must confront the issue of slavery to justify all the suffering and death it was causing.

Lincoln’s Emancipation Proclamation, issued in January 1863, freed very few enslaved people at first. The proclamation applied only to the 11 states that had seceded, not to the border states or areas in the South then under federal control. The document’s real power was symbolic, as it set the nation on the path to abolishing slavery completely.