River and coast defense was extremely important during the Civil War. Most navigable rivers in the South were defended by some sort of fortified position mounting heavy seacoast guns. The Cape Fear River was no exception, and its defenses ranged from simple batteries mounting one or two guns to huge fortifications mounting dozens of guns, like Fort Anderson. Fort Anderson's purpose was to prevent enemy warships from passing up the river and threatening Wilmington. In order for these defenses to be effective, planners and engineers had to select sites where the guns held an advantage over enemy ships.
Fort Anderson was constructed on the west bank of the Cape Fear atop part of the ruins of the colonial Port of Brunswick beginning on March 24, 1862. Lt. Thomas Rowland supervised the work. The structure was an earthen fort with walls six to ten feet high, stretching nearly a mile, from the Cape Fear River west to the headwaters of Orton Pond. Enslaved laborers, free blacks, and Confederate soldiers built the fort by hand. Within the walls stood the ruins of St. Philip's Anglican Church, an imposing brick structure with walls three feet thick and twenty-four feet high. To honor the church, Maj. William Lamb named it Fort St. Philip on May 11, 1862. On July 1, 1863 the name was changed to Fort Anderson in honor of Brig. Gen. George Burgwyn Anderson, who was mortally wounded at Antietam.
Major Lamb took a keen interest in engineering and fortification construction. Under his command the fort was enlarged and expanded. Lamb ordered the walls of the fort nearest the river increased in height to twenty-four feet, and added five gun emplacements and three underground magazines. The new battery was roughly L-shaped and was backed with buffer traverses twenty-six feet high. Lamb also ordered the construction of a new battery just to the north, which ran parallel to the river. This battery was twenty-six feet high and consisted of two magazines with a deep ditch in the rear. Construction was probably ongoing when Lamb was transferred to Fort Fisher on July 4, 1862 to oversee the construction there.
In addition to its location on a high bluff overlooking the Cape Fear, one of the most important considerations for Fort Anderson's strategic location was its position in relation to the river channel, through which warships would be forced to travel as they approached Wilmington. The narrow channel compelled advancing warships to pass close to the fort, putting them at a distinct disadvantage. An ample fresh water source nearby also enhanced the location.
Late in 1862, the fort was given the important assignment of acting as a quarantine station. Every blockade runner that entered the Cape Fear was required to stop at the fort to be checked for contagious diseases, illegal cargoes, and proper manifest records. The main cause for the quarantine station was the devastating epidemic of yellow fever that broke out in Wilmington in late summer to autumn of 1862.
MAP: Fort Anderson — Detailed structure map.
As part of the Cape Fear River defense system, Fort Anderson guarded the western approaches to Wilmington. During the Union advance on the port city, Fort Anderson was bombarded and captured, February 18-19, 1865. Wilmington fell on February 22.