petersburg was protected by fortifications known as the dimmock line, a line of earthworks long, east of the city, including 55 artillery batteries, and anchored on the appomattox river. the 2,500 confederates stretched thin along this defensive line were commanded by a former virginia governor, brig. gen. henry a. wise; the overall defense of richmond and petersburg was the responsibility of gen. p.g.t. beauregard, commander of the department of north carolina and southern virginia.