On June 18, 1778, after almost nine months of occupation, 15,000 British troops under General Sir Henry Clinton , the former U.S. capital.
The British had captured Philadelphia on September 26, 1777, following General George Washington’s defeats at the Battle of Brandywine and the Battle of the Clouds. British General William Howe had made Philadelphia, the seat of the Continental Congress, the focus of his campaign, but the Patriot government had deprived him of the decisive victory he hoped for by moving its operations to the more secure site of York one week before the city was taken.
While Howe and the British officer corps spent the winter enjoying the luxury of Philadelphia’s finest homes, the Continental Army froze and suffered appalling deprivation at Valley Forge. Fortunately for the Patriots, an infusion of capable European strategists, including the Prussian Baron von Steuben; the Frenchmen Marquis de Lafayette and Johann, Baron de Kalb; and Poles Thaddeus Kosciuszko and Casimir, Count Pulaski, aided Washington in the creation of a well-drilled, professional force capable of fighting the British.
The British position in Philadelphia became untenable after France’s entrance into the war on the side of the Americans. To avoid the French fleet, General Clinton was forced to lead his British-Hessian force to New York City by land. Loyalists in the city sailed down the Delaware River to escape the Patriots, who returned to Philadelphia the day after the British departure. U.S. General Benedict Arnold, who led the force that reclaimed the city without bloodshed, was appointed military governor. On June 24, the Continental Congress returned to the city from its temporary quarters at York, Pennsylvania.