Erwin L. Jordan, Jr, a black historian, estimates 65,000 served as Confederate soldiers and around 13,000 actually saw combat.
Ervin L. Jordan, Jr., is Assistant Professor and Associate Curator, Special Collections Department, University of Virginia Library. He is author of ‘Charlottesville’ and the ‘University of Virginia in the Civil War’ and, with Herbert Thomas, ‘Nineteenth Century Virginia Infantry’.
Jordan published his 447 page work ‘Black Confederates and Afro-Yankees in Civil War Virginia’ in 1995. The book has received some very high praise from reviewers.
Info on Erwin L. Jordan, Jr: http://www.upress.virginia.edu/books/jordan.html