Wilmington was the last major port open to the Confederacy on the Atlantic seacoast. Sometimes referred to as the "Gibraltar of the South" and the last major coastal stronghold of the Confederacy, Fort Fisher had tremendous strategic value during the war, providing a port for blockade runners supplying the Army of Northern Virginia. Ships leaving Wilmington via the Cape Fear River and setting sail for the Bahamas, Bermuda or Nova Scotia to trade cotton and tobacco for needed supplies from the British were protected by the fort. Based on the design of the Malakoff redoubt in Sevastopol, Russian Empire, Fort Fisher was constructed mostly of earth and sand. This made it better able to absorb the pounding of heavy fire from Union ships than older fortifications constructed of mortar and bricks. Twenty-two guns faced the ocean, while twenty-five faced the land. The sea face guns were mounted on 12-foot-high (3.7 m) batteries with larger, 45-and-60-foot (14 and 18 m) batteries at the southern end of the fort. Underground passageways and bombproof rooms existed below the giant earthen mounds of the fort. The fortifications kept Union ships from attacking the port of Wilmington and the Cape Fear River.

On December 23, 1864, Union ships under Rear Admiral David D. Porter commenced a naval bombardment of the fort, to little effect. On January 1865, the Union Army, Navy and Marine Corps successfully assaulted Fort Fisher. The loss of Fort Fisher compromised the safety and usefulness of Wilmington, the Confederacy's last remaining sea port. The South was now cut off from global trade. Many of the military supplies which the Army of Northern Virginia depended upon came through Wilmington; there were no remaining seaports near Virginia that the Confederates could use practically. Potential European recognition of the Confederacy was likely already impossible, but now became entirely unrealistic; the fall of Fort Fisher was "the final nail in the Confederate coffin." A month later, a Union army under General John M. Schofield would move up the Cape Fear River and capture Wilmington.