Vicksburg is the fifth volume in a series of historical novels spanning the Civil War featuring the Brannon family of Culpeper County, Virginia. The focus turns to the west and the Southern stronghold of Vicksburg, Mississippi, where Cory Brannon is working to keep the town supplied by wagon train and railroad from Texas. Vicksburg is the key to the Mississippi River and the future of the Confederacy, and Abraham Lincoln wants to put that key in his pocket. For almost a year the Federal army and navy have tried to dislodge the Confederates, but they have gained nothing. Finally, Union Gen. Ulysses S. Grant, the hero of the battles at Forts Henry and Donelson and the battle of Shiloh, is dispatched to take the town.