Siege of Yorktown

From September 28 to October 19, 1781, American and French forces under George Washington and the comte de Rochambeau besieged Lord Cornwallis at Yorktown, Virginia. Admiral de Grasse's fleet blocked British relief by sea after the Battle of the Chesapeake, while American and French troops opened trenches and captured key redoubts. Cornwallis surrendered more than 7,000 troops on October 19, 1781 in the most decisive allied victory of the war.

Yorktown resolved the military gamble created by Britain's southern campaign and by Washington's decision to move south from the Hudson in 1781. The siege showed that the French alliance could combine army, navy, and money in a way that finally trapped a major British field army. Politically, the surrender shattered British confidence that the war could be won at acceptable cost.

After Yorktown, Lord North's ministry fell in 1782 and peace negotiations moved forward in Paris. The surrender therefore led directly toward the Treaty of Paris of 1783, which recognized American independence and ended the war.