The Siege of Yorktown (sep 2, 1781 – oct 19, 1781)
On September 2nd, 1781, American and French forces began a siege of Cornwallis' forces at Yorktown. Cornwallis had chosen Yorktown as his defensive position because he thought its coastal position would be easy to retreat from. However, French fleets surrounded Yorktown, and eliminated Cornwallis' only route of escape. After only about a month of siege, Cornwallis was forced to surrender. Nearly 7,000 troops were captured as a result of this surrender.
General Cornwallis surrenders at Yorktown (Wikipedia).
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Important Events in the American Revolution