Here Washington's Continental army fought British forces under Lord Howe on September 11, 1777. Although the battle was an American defeat, the Continentals withstood the determined attack of British regulars, even while sustaining heavy losses. An American force of about 11,000 men, commanded by Washington, attempted to halt a British advance into Pennsylvania. The Americans were defeated near Chadds Ford on Brandywine Creek by approximately 18,000 British and Hessian troops under Howe. Casimir Pulaski, a Polish volunteer, commanded cavalry detachment helping to cover Washington’s retreat from Brandywine, September 11, 1777. As brigadier general, served September 1777 - March 1778 as first overall commander of the Continental Army’s cavalry. He was mortally wounded at the siege of Savannah, October 9, 1779.