Battle Of Yorktown Deception Strategy
by Lori S. Stewart, U.S. Army Intelligence Center of Excellence
November 1, 2022

On 19 October 1781, Lord Charles Cornwallis surrendered his British forces to General George Washington following a two-week siege at Yorktown, Virginia. Intelligence played a significant role in the battle that brought the American Revolution to its final climax.

 In late August 1781, Cornwallis marched his troops northward out of the Carolinas and set up defenses in Yorktown on the York River in the Chesapeake Bay. Meanwhile, General Washington had joined forces with those of the French Count de Rochambeau and moved their combined army of 9,000 to the Hudson River for a proposed attack on Sir Henry Clinton’s British forces in New York.

On 14 August, Washington learned that Admiral Francois de Grasse, with 3,000 French soldiers and twenty-nine warships, had sailed from the West Indies for the Chesapeake Bay. Seeing an opportunity to trap Cornwallis at Yorktown, Washington began moving his allied force southward. He left 2,500 men under the command of Maj. Gen. William Heath on the Hudson to keep Clinton distracted in New York.

Before leaving the New York area, Washington used deception operations to reinforce Clinton’s existing belief that Washington intended to attack New York. The American commander later wrote, “…much trouble was taken and finesse used to misguide & bewilder Sir Henry Clinton in regard to the real object….” To do so, Washington drafted a fake battle plan and grilled a known British spy about enemy forces and landing beaches on Staten Island, knowing the planted information would reach Clinton.

Washington then crossed his forces into New Jersey where, visible to the British, they set up a large camp complete with bread ovens, stockpiles of forage, and strategically positioned boats. When Washington was ready to move his army south, he kept even his senior commanders in the dark about their destination so word could not leak to British spies. Clinton and his intelligence network, knowing Washington’s proclivities for deception, interpreted Washington’s march out of the New York area as a ruse, certain he would double back to attack the city.

On 14 September, Washington arrived at the Marquis de Lafayette’s headquarters at Williamsburg, approximately seven miles from Yorktown. A week earlier, Admiral de Grasse had arrived in the Chesapeake Bay in time to run off nineteen warships of the British Fleet and block Cornwallis in the bay. Worried that Cornwallis might cross the York River to Gloucester and steal away before Washington arrived, Lafayette had fed him disinformation. James Armistead, a slave permitted by his master to join the Continental Army, had already been working as a double agent for Cornwallis but was loyal to Lafayette.

In late August, Armistead provided the British commander with false reports inflating the strength of Lafayette’s force. Additionally, Pvt. Charles Morgan, a member of a New Jersey light infantry battalion posing as a deserter, informed Cornwallis that Lafayette had enough boats to send his entire force across the river after the British forces if they tried to evacuate Yorktown.

Convinced he was outnumbered, Cornwallis fortified his position in Yorktown and requested assistance from New York. Clinton, however, convinced of an imminent attack on New York City, failed to send reinforcements until it was too late.

On 6 October, Washington had at his command 16,000 soldiers as he laid siege to the 7,000 British forces at Yorktown. After two weeks of nearly continuous bombardment, Cornwallis surrendered on 19 October. This ended major operations of the American Revolution and cemented Washington’s reputation as a master of deception.

Our Valiant Troops | I Am The One | Veterans | Citizens Like Us

U.S. Army Intelligence Center of Excellence | U.S. Army | U.S. Army Gifts | U.S. Department of Defense