The Siege of Charleston: An Entire Army Lost

After the war stalemated in the North following Monmouth, the British shifted their strategic focus south, betting that Loyalist sentiment in the Carolinas and Georgia could be rallied to reconquer the rebellious colonies from below. The campaign opened with a six-week siege of Charleston, South Carolina, that ended in the single worst American defeat of the Revolutionary War: an entire Continental army of roughly 5,000 men surrendered on May 12, 1780. Benjamin Lincoln, the American commander, later compiled his own papers documenting the siege, now held at the Library of Congress. Washington's correspondence as the disaster unfolded survives at Founders Online.

Sir Henry Clinton sailed from New York the day after Christmas 1779 with roughly 8,500 troops, escorted by warships, intending to seize Charleston and use it as a base to reclaim the southern colonies through a combination of military pressure and appeals to Loyalist sympathizers. The voyage south was stormy and difficult, and the fleet did not reach the Charleston area until February. Washington, occupied with defending against a possible attack on New York, could offer Lincoln little beyond warnings of what was coming.

Lincoln worked through the early months of 1780 to repair Charleston's deteriorating fortifications, but the city's defenses, particularly on the landward sides, remained incomplete when Clinton's army crossed the Ashley River on March 29 and began constructing siege works in front of the American lines.

As April progressed, British warships ran past Fort Moultrie at the harbor mouth, cutting off Charleston's last realistic route of escape or resupply by sea. Washington, reading Lincoln's increasingly grim reports from a distance, wrote to Lieutenant Colonel Henry Laurens with a forecast that proved entirely accurate.

By late April, Continental engineer Brigadier General Louis Duportail had arrived to assess the city's defenses directly and concluded Charleston was no longer defensible, urging immediate evacuation before the British completed their encirclement. South Carolina's civilian leadership, led by Lieutenant Governor Christopher Gadsden, pressured Lincoln to hold the city regardless, making an organized military withdrawal politically impossible even after it had become militarily necessary.

By May 8, the opposing lines stood only yards apart. Clinton demanded unconditional surrender. Lincoln refused, and Clinton responded by ordering the city bombarded with heated shot, setting fires throughout Charleston. As civilian morale collapsed under the bombardment, Charleston's own residents petitioned Lincoln to accept whatever terms the British would allow. Lincoln later described the final days of the siege in his own words.

Lincoln formally surrendered the city and his army on May 12, 1780. The terms denied his Continental soldiers the honors of war, the formal ceremonial recognition typically extended to a defeated army that had fought honorably, a humiliation Lincoln had specifically tried and failed to negotiate against. Roughly 1,800 able-bodied Continental troops marched out under guard, their colors cased rather than displayed, to begin imprisonment that many would not survive.

The loss of an entire field army was the costliest single defeat the United States suffered in the war. But the British strategic premise, that capturing Charleston would trigger a broad Loyalist uprising capable of pacifying the South, proved badly mistaken. No such uprising materialized at the scale Clinton had hoped for. Instead, the countryside descended into a brutal and prolonged partisan war between Patriot militia and Loyalist forces that would define the next two years of fighting in the Carolinas.