After capturing New York City, British General William Howe (1729–1814) set out to seize the Hudson River Val ley and isolate New England from the rest of the colonies. His efforts kept George Washington (1732–1799), commander in chief of the Continental army, occupied in 1777 and 1778. Howe's mission was part of a three-pronged plan for British victory in America. The other two targets were Canada (a cam paign handled by British generals Guy Carleton and John Bur goyne) and the Southern Colonies (a land and sea expedition planned for 1778–79 and headed by General Henry Clinton, who succeeded Howe as commander in chief of British forces in America in May 1778).

In January 1777, after his completely unexpected vic tories at Trenton and Princeton, New Jersey, George Washing ton had settled in for a miserably uncomfortable winter at Morristown, New Jersey. Meanwhile, Howe and...