Part of the Cape Fear River Defenses, Fort Anderson, along with Fort Fisher, protected the port of Wilmington. It was essential that Wilmington remain open and in Confederate hands as goods and supplies entering the port via blockade runners were transported by rail to Lee's army in Virginia. Fort Anderson provided protection for these blockade runners. Constructed by manual labor, Fort Anderson was a large sand fortification, which had two batteries, each with five cannons overlooking the shipping channel.
In February 1865, once Fort Fisher fell, Union forces repositioned themselves to attack Fort Anderson from both the land and the river. After three days of fighting, the Confederate forces evacuated the fort at night. Union gunboats started firing at first light, unaware that their own federal forces were entering the fort from the land face. The federal infantry frantically waved white sheets and blankets to stop the deadly fire from their own forces.