Who won the Battle of Princeton?
The Americans won. On 3 January 1777, in the American Revolutionary War, George Washington slipped away from Lord Cornwallis at Trenton by night and struck the British rear guard at Princeton, New Jersey. Charles Mawhood's redcoats broke Hugh Mercer's brigade, but Washington rallied his men and routed them within about an hour.3
Anniversary 3 January 2027 marks the 250th anniversary of the Battle of Princeton; see the whole campaign in The Ten Crucial Days.
Just over a week after crossing the Delaware to win at Trenton, George Washington was trapped again. Lord Cornwallis had pinned his army against a creek, with no boats to escape across the river behind it, and meant to finish it in the morning. That night Washington's army vanished. At sunrise it was on the fields south of Princeton, and within an hour it had broken British regulars in the open for the first time in the war.4
Part of The greatest battles of the American Revolution · Before: Battle of Trenton · Next: The Battle of Brandywine
Trapped at the Assunpink
The autumn of 1776 had been a catalog of American disasters: Long Island, the loss of New York, the fall of Fort Washington and a long retreat across New Jersey into Pennsylvania. Then, on 26 December, Washington crossed the Delaware and captured the Hessian garrison at Trenton. Eager to build on the victory, he crossed back into New Jersey on 30 December and set up his headquarters at Trenton again, beside the bridge over Assunpink Creek.5 › Battle of Trenton, 1776
The British reacted fast. Lord Cornwallis marched from Princeton on 2 January 1777 with, by Britannica's count, about 7,000 troops, but American skirmishers slowed him so badly that a three-hour march took most of the day. By the time he reached Trenton, Washington had drawn up a strong line on the south bank of the creek. Cornwallis threw a series of attacks at the bridge as darkness fell; they were beaten back by American musketry and artillery, and at nightfall the American line still held. The fight is remembered as the Second Battle of Trenton, or the Battle of the Assunpink.6
Cornwallis decided to wait for daylight. The National Park Service's landmark study records that he ignored advice from Sir William Erskine to attack at once, convinced that the Americans had nowhere to go. He had reason to think so. A thaw had broken up the ice on the Delaware, so Washington could not cross back into Pennsylvania, and the British held the main roads to the northeast.7
The night march
That night Washington called a council of war and proposed something bold: instead of waiting to be attacked, the army would slip away and strike the British rear guard at Princeton, about ten miles to the northeast. A small party stayed behind to keep the campfires burning, dig, fire an occasional shot across the creek and make enough noise to persuade the British that the whole army was still there.8
The main army left around two in the morning. It avoided the main road, which the British had fortified, and took a little-known back route by Quaker Road and Sawmill Road that approached Princeton from the south. A sharp drop in temperature had hardened the muddy track enough to carry the guns. The army marched on whispered orders, and by sunrise it was a mile and a half south of the town.9
The armies
Washington had about 4,500 men, most of them the same tired, poorly clothed Continentals and militiamen who had crossed the Delaware a week earlier, with some 35 guns according to the American Battlefield Trust. At Princeton Cornwallis had left his reserve, the 4th Brigade under Lieutenant Colonel Charles Mawhood: the 17th, 40th and 55th Regiments of Foot, a detachment of light dragoons and a mixed body of recruits and convalescents, about 1,200 men in all, with a battery of eight guns.10
Mawhood had orders to leave Princeton that very morning and join Cornwallis at Trenton, so when the Americans appeared, part of his force was already on the road south. Neither side planned to fight where the battle took place; it began as a chance collision.11
Collision at Clarke's orchard
At daybreak the American column was passing the farms of the Quaker brothers Thomas and William Clarke when British troops on the high ground beyond Stony Brook spotted it. Mawhood turned back across the brook to attack. Washington detached Brigadier General Hugh Mercer with a few hundred men, many of them riflemen, to screen the main column and delay the British, and Mercer's men raced the redcoats for the cover of an orchard on William Clarke's farm.12
The two forces met at the orchard fence at about half past eight, by Britannica's timing. The first exchange of fire favored the Americans, but the riflemen had no bayonets and loaded more slowly than men with muskets. Mawhood dressed his line and ordered a bayonet charge, and Mercer's brigade broke.13
Mercer falls
Mercer was trying to rally his men when his horse was shot from under him. According to the American Battlefield Trust, the British, mistaking him for Washington, called on him to surrender; he drew his sword instead, was clubbed with a musket butt, bayoneted seven times and left for dead. He was carried to the Thomas Clarke house, which became a field hospital, and died there nine days later, on 12 January, despite the care of Dr. Benjamin Rush.14
His fall shaped the battle's image ever after. John Trumbull painted the moment, with Mercer on the ground beside his horse and Washington riding up behind him, and an oak near the spot became known as the Mercer Oak, a landmark of the battlefield that no longer stands.15
Washington rallies the line
The crisis was real. Washington sent John Cadwalader's Philadelphia Associators, militiamen who had never been in a stand-up fight, to fill the gap, but Mercer's fleeing men tumbled through their ranks and the British bayonets broke them too. Mawhood pushed on, threatening to cut the American column in two. Only Captain Joseph Moulder's battery of guns, firing grapeshot and canister from the shoulder of the ridge, kept the British from rolling up the line.16
Then Washington rode into the fight himself. New Jersey's state park service describes him riding his horse between the British and American lines. The American Battlefield Trust records him calling, "parade with us my brave fellows! There is but a handful of the enemy, and we will have them directly." He led the reformed troops to within about thirty yards of the British line before ordering them to fire. Both lines fired at once, and when the smoke cleared Washington was still in the saddle, unhurt.17
Fresh brigades came up on both flanks, Thomas Mifflin's on the left and those of Daniel Hitchcock and Edward Hand on the right, and the British line gave way. Mawhood's men fled across the fields toward Stony Brook and the road to Trenton. Britannica records the story that Washington spurred after them crying, "It is a fine fox chase, my boys!"18
Nassau Hall
Closer to the town, John Sullivan's leading brigades met the 55th and 40th Regiments. The 55th fell back once fugitives from Mawhood's force reached it, and the 40th was swept out of a ravine called Frog Hollow. Some of the British retreated into Nassau Hall, the great stone building of the College of New Jersey, today Princeton University, and barricaded themselves inside.19
The siege did not last long. American artillery fired a few rounds into the building, and the garrison surrendered. Britannica names the young artillery captain Alexander Hamilton as the officer directing the guns, while calling the story that one of his shots destroyed a portrait of King George II inside the building probably apocryphal.20
How many died at the Battle of Princeton?
No exact count survives. Britannica puts the dead at perhaps two dozen on each side, with about twice as many wounded and nearly 200 British captured. The American Battlefield Trust estimates about 75 to 80 American casualties against roughly 270 British, or some 230 British killed and wounded plus about 250 captured.21
The whole battle had lasted about an hour. Older counts run higher: the National Park Service's 1975 landmark study gives 400 to 600 British killed, wounded and captured against about 30 Americans, a disproportionate number of them officers. Hugh Mercer was the most prominent of the American dead.22
The escape to Morristown
At Trenton, Cornwallis woke to find the American lines empty and heard the guns at Princeton. He marched back in a hurry. The Americans held the town until the British were close, plundered the British baggage, and then destroyed the bridge over Stony Brook, which slowed the pursuit just as the rear guard was marching out.23
Washington would have liked to push on to New Brunswick, where the British kept a war chest that the landmark study puts at £70,000. But his men were exhausted after a night march and a battle, and Cornwallis was close behind. Instead the army turned north at Kingston into the hills of Morristown, where it went into winter quarters on 6 January.24
Why was the Battle of Princeton important?
Princeton completed the turnaround that Trenton began. For the first time the Continental Army broke British regulars in the open field. The victory renewed confidence in Washington and his troops across the colonies, and soon afterward the British gave up most of New Jersey, which they had overrun only weeks before.25
The military results were out of all proportion to the numbers engaged. With Washington established in northern New Jersey, less than three days' march from New York, Cornwallis abandoned Trenton and fell back to New Brunswick, and the British gave up most of the state they had overrun that autumn. In ten days the Continental Army had crossed the ice-choked Delaware three times, fought three battles and come out on top in each.26 › The Ten Crucial Days, 1776 to 1777
The effect on morale was greater still. Trenton and Princeton came when, in the words of the landmark study, the spirits of the American people had reached "a dangerously low ebb". They renewed confidence in Washington as a commander, at home and abroad, and showed that an army of amateurs could beat seasoned British troops in the open field. Mawhood was praised for holding the Americans long enough to save most of his supplies, and King George III honored the 17th Foot for its stand.27
The battlefield today
The heart of the battlefield, the fields where Mercer fell and Washington rallied the army, is preserved as Princeton Battlefield State Park, on Mercer Road at the southern edge of the town. The Thomas Clarke house, where Mercer died, still stands on a low rise in the park. Across the road a monument marks the burial place of British and American dead.28
The battle is woven into the town as well. Nassau Hall, which the British held to the last, still stands on the Princeton campus, although two later fires changed much of its appearance, and the nearby Stony Brook bridge on the Trenton road is the successor of the one Washington's men tore down.29 › Battle of Monmouth, 1778
