In March 1776 the British forces of General William Howe withdrew from Boston after Major General George Washington fortified high ground threatening the city and its harbor. With this army augmented by reinforcements from Europe, General Howe captured New York City, forcing Washington to retreat all the way across New Jersey. At the end of 1776, Washington crossed the Delaware River and surprised German troops at Trenton, New Jersey, and eventually regained control of most of the state. The two armies then settled into winter quarters, although there was much skirmishing before the 1777 campaign got underway.