After the successful coup at Trenton, Washington recrossed the Delaware into Pennsylvania with his Hessian prisoners. But he reoccupied Trenton on 30 - 31 December 1776, and collected there a force of 5,200 men, about half militia. Meanwhile, Maj. Gen. Charles Cornwallis, British commander in New Jersey, who was in New York at the time of the attack on Trenton, returned gathering troops as he came. He entered Trenton with some 6,ooo British regulars on 2 January and faced Washington's forces, which had withdrawn southward behind Assunpink Creek. The Americans were in a most precarious position with their backs to the Delaware.
Fortunately, Cornwallis delayed his attack until the following morning. This gave Washington's men an opportunity to steal off quietly by a side road during the night of 2 - 3 January, leaving their campfires burning brightly. They slipped southward and eastward undetected around the enemy's flank and by morning of the 3rd had arrived at Princeton, where they encountered a column of British regulars led by Col. Charles Mawhood just leaving the town to join Cornwallis. In a brief engagement the Americans defeated the British, inflicting losses of 400-600 killed, wounded, and prisoners at a cost of 30 patriots killed and wounded. Mawhood's force retired in disorder toward Trenton and New Brunswick while Washington moved on north to Morristown, where thickly wooded hills provided protection against a British attack. Here he established his winter headquarters on the flank of the British line of communications, compelling General Howe to withdraw his forces in New Jersey back to New Brunswick and points eastward.