Born in 1826 in Virginia, William Mahone graduated from the Virginia Military Institute, taught at a military academy, and by 1861 was the president of the Norfolk and Petersburg Railroad. In November 1861 he was promoted to brigadier general and served with his brigade from Seven Pines to the Crater, missing only Antietam.

Mahone's performance at the Crater earned him an on-the-spot promotion by Gen. Lee to major general. During the course of the siege Mahone was one of the most effective divisional commanders of either side. His troops, who were engaged in Jerusalem Plank Road, the Crater, Weldon Railroad, Reams Station, and Burgess Mill, captured thousands of Union soldiers and a number of colors and cannons.

With the surrender, Mahone returned to the presidency of the Norfolk and Petersburg Railroad, served as mayor of Petersburg, and served as a U.S. Senator for a term. For a period of time the control of Virginia state politics was virtually in Mahone's hands. He died in 1895.