Which French naval commander helped trap the British fleet at Yorktown in 1781?

The Comte de Grasse helped trap the British fleet at Yorktown in 1781.

François Joseph Paul de Grasse commanded the French fleet that entered the Chesapeake Bay during the Yorktown campaign. His ships defeated or blocked the British relief fleet at the Battle of the Chesapeake, also called the Battle of the Virginia Capes, on September 5, 1781.

That naval result was essential to the siege. By controlling the bay, de Grasse prevented the British army under Charles Cornwallis from receiving effective reinforcement or escaping by sea. He also brought French troops and supplies that strengthened the allied operation on land.

De Grasse worked with George Washington and the French army commander Comte de Rochambeau. Rochambeau led French land forces, while de Grasse commanded the naval force. This distinction matters because both men held French noble titles and were major contributors to the Yorktown victory, but only de Grasse led the fleet that closed the Chesapeake.