Fort Constitution, later Fort Lee, was constructed atop the New Jersey Palisades, beginning in July 1776. Its sister garrison, Fort Washington, occupied an elevated position across the Hudson River on Manhattan. Together the guns of the two strongholds were intended to frustrate the British war plan: Control the Hudson River with the Royal Navy to cut the colonies in two, then suppress the rebellion, first in New England and elsewhere if necessary.
The New Jersey garrison later took the name of Fort Lee to honor Charles Lee, then regarded by many as Americas most able soldier. Ships were sunk in the waters between the two forts as an additional means to prevent British passage on the Hudson.
Fort Lee, however, never saw the opportunity to play its intended role. The fall of the larger and stronger Fort Washington on November 16 made the New Jersey location untenable. On November 20, more than 4,000 British soldiers under Lord Charles Cornwallis crossed the Hudson about six miles north of Fort Lee, in hopes to trap the American army between the Hackensack and Hudson rivers.
George Washington sent word of the British advance to the Continental Congress and suggested that Philadelphia would likely become the next target. The news came as a shock to many of the delegates, who had failed to grasp how badly the war was going.
When Cornwalliss forces arrived at Fort Lee, they encountered no opposition. Nathanael Greene had led a hurried evacuation of the facility and marched his soldiers toward Hackensack, where he joined Washington. The British were delighted to find 50 cannon, huge stores of flour and ammunition, and vast quantities of other supplies left behind by the fleeing Americans.
Believing he had to the opportunity to strike a decisive blow against the rebels, Cornwallis pursued Washingtons army. The American army, already in dreadful condition, was further depleted on November 30 when more than 2,000 militiamen from Maryland and New Jersey reached the end of their enlistment terms and went home. Washington sent repeated pleas to Charles Lee to join him. Lee failed to respond, hoping for Washingtons defeat and his own ascent to command.
Washingtons forces retreated across New Jersey, barely managing to keep a step ahead of Cornwallis. In early December, the Americans collected a small flotilla of boats along the Delaware River and burned those they could not use. On the 11th, Washington crossed the river into Pennsylvania; the first British soldiers entering Trenton watched the last Americans rowing for their lives. Two days later, the tardy Lee, who at last was coming to Washingtons aid, was surprised and captured at Basking Ridge, New Jersey. His army, which also had suffered from enlistment expirations, was taken over by General John Sullivan, who led them to Pennsylvania to join Washington.
Congress ended its agonizing about whether to stay or go on December 12 and departed from Philadelphia. On the 20th they convened in Baltimore.
However, British commander Major General William Howe called a halt to Cornwalliss offensive in mid-December. Howe preferred to concentrate his attentions on the commercial center of Newport, Rhode Island, which had been occupied without opposition two weeks earlier, and on preparations for the winter encampment.
Before settling into his winter quarters, Washington would provide a badly needed boost in morale by striking at Trenton and Princeton.