A dramatic real-life adventure story, "Unspoiled Heart" chronicles the Civil War experiences of Charles P. Mattocks, a major in the Union Army of the Potomac. From 1863 to 1865, Mattocks kept a diary in which he meticulously recorded the everyday details of army politics and camplife and the excitement of commanding men in battle.

At the tender age of twenty-three, this Bowdoin College graduate took successive command of the Seventeenth Maine and the famous First United States Sharpshooters. With an "unspoiled heart," he fearlessly led his troops in the crucial battles of Chancellorsville and Gettysburg as well as in several minor skirmishes. During the Battle of the Wilderness, Mattocks was captured, imprisoned by the Confederates, and escaped into the mountains of North Carolina, where he was recaptured by Confederate Indians.

After nine months in different Confederate prisons, Mattocks was exchanged in time to participate in the Battle of Sayler's Creek, in which his bravery earned him the Congressional Medal of Honor.

Mattocks's journals are rich with insightful commentary, including details about the officers' prisons in Georgia and the Carolinas and about the anti-Confederate slaves and white Unionists who aided him in his escape. Of particular interest are his invaluable descriptions of Sayler's Creek, the last great battle involving the Army of the Potomac and one that has often been neglected in Civil War literature.