Enslaved Blacks were relied on disproportionately to support he confederate war machine but not as soldiers. They were tasked as teamsters, launderers, cooks and other camp support. They were also responsible for making up the difference for homefront laborers who were off to fight the war. None of them volunteered for the duties they were assigned. They were still slaves.

Towards the end of the war the idea of black conscripts being given their freedom for service was floated and an unsuccessful attempt to raise two units was made.

If you want a story about heroic black men in the Civil war look into the Mass. 54th portrayed in the movie Glory.