Based on nearly five decades of research, this work is a biographical register and analysis of the people who most directly influenced the course of the American Civil War, its high commanders. Numbering 3396, they include the presidents and their cabinet members, state governors, general officers of the Union and Confederate armies (regular, provisional, volunteers and militia), and admirals and commodores of the two navies. Errors of fact and interpretation concerning the high commanders are legion in the Civil War literature, in reference works as well as in narrative accounts. The present work brings together for the first time in one volume the most reliable facts available, drawn from more than 1,000 sources and including the most recent research. The biographical entries include complete names, birthplaces, important relatives, education, vocations, publications, military grades, wartime assignments, wounds, captures, exchanges, paroles, honors, and place of death and interment.