French sea power, which George Washington termed "the pivot upon which everything turned," compelled the capitulation of the British Army at Yorktown,  thus setting the final course for success in America's struggle for independence. Knowledge that a powerful French Fleet, under French Admiral Francois Joseph  Paul DeGrasse,  was sailing from the West Indies for the Chesapeake, led the General's Washington and Rochambeau to  break camp around New York and march south. The subsequent naval battle off the Virginia Capes, in which  DeGrasse drove off the British Fleet of Rear Admiral Thomas Graves, sealed the fate of General Lord Cornwallis entrenched at Yorktown, with his back to the sea. Hemmed in on the land side by the allied armies, and cut off from support or evacuation by water, Cornwallis surrendered over seven thousand troops on 19 October 1781. The final victory went to the holder of the sea lines of communication.