The Battle of Fort Washington was fought in New York on November 16, 1776, during the American Revolutionary War between the United States and Great Britain. It was a British victory that gained the surrender of the remnant of the garrison of Fort Washington near the north end of Manhattan Island. It was one of the worst Patriot defeats of the war.^[38]

After defeating the Continental Army under Commander-in-Chief General George Washington at the Battle of White Plains, the British Army forces under the command of Lieutenant General William Howe planned to capture Fort Washington, the last American stronghold on Manhattan. General Washington issued a discretionary order to General Nathanael Greene to abandon the fort and remove its garrison – then numbering 1,200 men^[39] but which later grew to 3,000^[40] – to New Jersey. Colonel Robert Magaw, commanding the fort, declined to abandon it as he believed it could be defended from the British. Howe's forces attacked the fort before Washington reached it to assess the situation.

Howe launched his attack on November 16. He led an assault from three sides: the north, east and south. Tides in the Harlem River prevented some troops from landing and delayed the attack. When the British moved against the defenses, the southern and western American defenses fell quickly, and the obstacles meant to deter an attack were bypassed with ease.^[41] Patriot forces on the north side offered stiff resistance to the Hessian attack, but they too were eventually overwhelmed. With the fort surrounded by land and sea, Colonel Magaw chose to surrender. A total of 59 Americans were killed in action and 2,837 were taken as prisoners of war.

Three days after the fall of Fort Washington, the Patriots abandoned Fort Lee. Washington and the army retreated through New Jersey and crossed the Delaware River into Pennsylvania northwest of Trenton, pursued as far as New Brunswick, New Jersey by British forces. The British consolidated their control of New York Harbor and eastern New Jersey.