Many of those who served with George Washington in the French and Indian War also served during the Revolutionary War. Some of his former comrades, like Thomas Gage, served the British in both conflicts and were Washington’s enemies in the Revolution. Others, Horatio Gates and Adam Stephen for instance, later served with Washington against the British. Hugh Mercer enjoyed a personal relationship that started in the French and Indian War, lasted throughout the time between the two conflicts, and ended in battle alongside Washington in the Revolution.
Born in Scotland in 1726, Mercer attended Aberdeen University and became a doctor. Supporting his native land, he was forced to flee after the Battle of Culloden ended the Jacobite rising of 1745; he sailed to America in 1747. He first lived in Pennsylvania and practiced medicine on the fringe of the settlements. During the French and Indian War, Mercer helped treat the survivors of Edward Braddock’s debacle along the Monongahela River. Inspired by the sight of the wounded, Mercer joined the Crown’s forces, ironically the enemy he had fought in Scotland.
In 1756 Mercer took part in John Armstrong’s attack on the village of Kittanning, a staging point for Indian raids on the Pennsylvania frontier. A story, possibly apocryphal, tells that Mercer, severely wounded and separated from his troops, made his way painfully one hundred miles to the nearest British garrison. He served in many actions including the Forbes Expedition and as commandant of Fort Pitt.
During the French and Indian War, Mercer met and befriended George Washington. After the war, Mercer moved to Fredericksburg, across the Rappahannock River from Washington’s family home at Ferry Farm. Mercer opened an apothecary shop and joined Washington’s Masonic lodge. He married Isabella Gordon and raised five children.
After Washington married Martha Custis and moved to Mt. Vernon, Mercer spent a good deal of time there, primarily in his role as physician to Martha’s daughter Patsy who suffered from epilepsy. Mary Washington, George’s mother, was another of Mercer’s patients.
George Washington’s boyhood home at Ferry Farm passed to his mother in 1754. Mary Washington lived on the farm until age forced her to move into a small house in Fredericksburg in 1772. Hugh Mercer made a deal with George Washington to purchase the farm in 1774.
An indication of his important position in the community, Mercer was elected colonel of the militia of four counties when hostilities were opened with Great Britain. His career had come full circle: fighting against Britain with Bonnie Prince Charlie, fighting for Britain against the French, and again fighting Britain in defense of colonial liberties.
Mercer transitioned from militia officer to Continental Army officer when his Virginia troops became part of the main army, receiving his commission as a brigadier general on June 5, 1776. Mercer was given command of the “Flying Camp” in New Jersey. The Flying Camp was designed to provide a strategic reserve for the main Continental forces in New York, serving as a staging area for various militia units and other troops that would be called upon to reinforce the main army or serve in other capacities.
At first the assignment to command the camp seemed exciting and a great opportunity. Mercer had large numbers of men and some of excellent quality. With such resources, he planned an operation to attack the British who had recently taken Staten Island at the point known as New Blazing Star. Events and weather ended that action with only a few prisoners taken. Mercer was unable to mount other operations; as the Continental Army suffered defeats around New York, troops from the Flying Camp were siphoned off for the main army. The Flying Camp was dissolved and Mercer joined Washington.
Mercer commanded a brigade in the Battle of Trenton, serving with Nathaniel Greene’s Division. A few days later, Mercer again led his brigade across the Delaware, participating in the Second Battle of Trenton along Assunpink Creek. After the battle, Washington’s forces seemed trapped with Lord Cornwallis to his front and the Delaware cutting off his retreat. Fortunately, Cornwallis hadn’t tightened the noose completely.
That night Washington pulled off his famous escape on a back road, moving off around Cornwallis’s flank and making for Princeton. As the Continental Army made its way north, Mercer’s force was detailed from the main column to destroy the Post Road Bridge over the Stony Brook off to the left of the main advance. The rest of the column continued on to Princeton. The brigade, about 300 men, moved toward the bridge but scouts spotted a party of British troops from Princeton moving into a position to place themselves between the two American columns. Mercer acted quickly, facing his troops to the right and bringing them on line. The brigade, made up of men from Virginia, Delaware, and Maryland, moved toward an orchard where the British with two cannons were moving in to attack the other American column.
Halting his men, Mercer ordered them to fire. The Continentals fired, halting the British and forcing them to form a line to answer. A second volley spewed from the guns of Mercer’s brigade before the British could reply. Momentarily checked, the British quickly recovered and fired, then charged. Lacking bayonets, most of Mercer’s men fell back. With the British pressing their advantage, Mercer rode into the midst of his retreating men and tried to reform a line.
Mercer’s horse was injured and the general found himself dismounted as the British reached his position. Surrounded, he tried to defend himself, but was clubbed to the ground after he ignored calls for his surrender. The King’s troops proceeded to stab his prostrate body at least six times before leaving him for dead. Col. John Haslet, commander of the veteran Delaware troops, tried to assume command and was killed instantly by a shot to the head.
Washington arrived with reinforcements and the outnumbered British were defeated. The Continental forces could not enjoy their victory, pushing on through Princeton, quickly ransacking British supplies, and moving on into northern New Jersey before Lord Cornwallis and the main British Army could catch them. In leaving the battlefield, the colonials left their wounded, including General Mercer. A British surgeon’s mate and several local women took care of both British and American wounded at the nearby home of Thomas Clarke.
Thinking Mercer was dead, Washington included his loss in a letter proclaiming Princeton as a victory to President John Hancock:
This piece of good fortune is counterbalanced by the loss of the brave and worthy Genl Mercer, Cols Hazlet and Potter, Captn Neal of the Artillery, Captain Fleming who commanded the first Virginia Regiment and four or five other valuable Officers who with about twenty five or thirty privates were slain on the field-
Receiving news that Mercer was alive and being cared for, Washington sent a note to Cornwallis requesting an officer be allowed to visit the wounded general, noting to Israel Putnam that, “… General Mercer is badly wounded if not mortally-“
Benjamin Rush, the accomplished Philadelphia physician, went to Princeton and attended to Mercer.
Mercer lingered on, painfully succumbing to his wounds on January 12. On January 15 Washington, unaware of his death, inquired after his health in a letter to Joseph Reed, president of the Pennsylvania State government. By the time Washington learned of Mercer’s death, his body had been taken for burial to Philadelphia.
After Mercer’s death, Congress voted a monument to him but made no allowance to erect it. A privately funded memorial was constructed over his grave in Philadelphia in 1840. Finally, in 1906, the U.S. government erected a monument on Fauquier Street in Fredericksburg not far from Kenmore, George Washington’s sister Betty Lewis’ home. John Trumbull painted Mercer’s death as one of his series on the deaths of various generals in the Revolution, all similar to Benjamin West’s Death of Wolfe. Four counties, several towns and streets were named after him. His college, Marschal at the University of Aberdeen, chose him as one of its distinguished alumni. During the Revolution, one of the forts protecting Philadelphia, at Red Bank in New Jersey, was named for Mercer. A fierce battle took place at Fort Mercer October 22, 1777 that resulted in a defeat for Britain’s German allies. The fort was later abandoned.
Today the state of New Jersey maintains a beautiful park at the Red Bank site with a small monument to Mercer and another to Fort Mercer’s commander, Christopher Greene. A recent visit to the site revealed many locals enjoying the various picnic and play areas but the large number of visitors to the original fortifications ignored the monuments, original entrenchments and period artillery. They were busy chasing Pokemon!
 John Goolrick, The Life of General Hugh Mercer (The Neale Published Company, New York, 1906), 27.
 Open to the public today, see http://www.washingtonheritagemuseums.org/
 Donald Jackson, ed., The Diaries of George Washington, vol. 2, 1766-70, Colonial Series, vol. 6, 4 September 1758-26 December 1760 (University Press of Virginia, Charlottesville), 122,123, 126, 253, and 261.
 W. W. Abbot and Dorothy Twohig, ed. Papers of George Washington, Colonial Series, vol. 10, 21 March 1774 – 15 June 1775 (Charlottesville: University Press of Virginia, 1995), 2–3.
 Philander D. Chase and Frank E. Grizzard, Jr., ed. The Papers of George Washington, Revolutionary War Series, vol. 6, 13 August 1776 – 20 October 1776 (Charlottesville: University Press of Virginia, 1994), 577–578.
 Account of the Battle of Princeton from Philander P. Chase, ed., The Papers of George Washington, Revolutionary War Series, Vol. 7, October 1776-January 1777 (University of Virginia Press, Charlottesville, 1997), 519-530.
 Ibid, 521.
 Ibid, 535.
 Frank Grizzard, Jr., ed., The Papers of George Washington, Revolutionary War Series, Vol. 8, January-March 1777 (University Press of Virginia, Charlottesville, 1998), 76.
 John Trumbull, Catalogue of Paintings, by Colonel Trumbull; Including Eight Subjects of the American Revolution, with Near Two Hundred and Fifty Portraits of Persons Distinguished in That Important Period. Painted by Him from the Life (New Haven, CT: Gallery of Yale College, 1835), 19–22.