Following the British capture of New York City in a 1776 campaign, British commander Lieutenant General General William Howe turned his thoughts to capturing the seat of the Second Continental Congress, Philadelphia. In July 1777 he embarked about 18,000 troops on transports in New York, and sailed to the northern reaches of the Chesapeake Bay. Landing his troops there in late August, he defeated the Continental Army of General George Washington at the September 11 Battle of Brandywine, and occupied Philadelphia without opposition on September 25 after Washington was forced to retreat west of the city.