Black people from both the North and the South participated in the Civil War in a variety of ways. Free blacks from the North tried to join the fight as soldiers from the earliest days of the conflict. These men not only wanted to help free the slaves in the South, but also felt that they could improve their chances of gaining equal rights in American society by proving their patriotism and courage on the battlefield. But prejudice (unfair treatment because of their race) prevented blacks from enlisting in the Union Army until late 1862. It also created racial conflicts with working-class whites in many Northern cities during the war years.

In the South, black slaves performed much of the heavy work that was required to prepare the Confederacy for war. They built forts, dug trenches, hauled artillery and supplies, set...