American History

Hugh Mercer – The Jacobite Patriot

Hugh Mercer, mortally wounded at the Battle of Princeton, is one of the most fascinating figures of the early Revolutionary War. This is the story of his journey - from fighting as a young medic in the Jacobite ranks at Culloden (1746) to his final battle on the outskirts of Princeton.

Today, January 3, is the anniversary of the Battle of Princeton. During the course of the battle, America gained one of her first martyrs, Brigadier-General Hugh Mercer. This is his story.


Hugh Mercer was born on January 16, 1726, in the little fishing town of Rosehearty, along the north coast of Aberdeenshire. His father, William, was a Presbyterian minister, while the origins of his mother, Anne Munro, are slightly more mysterious. The traditional accounts of Hugh Mercer’s life record her as the daughter of Sir Robert Munro, a war hero who had earned great distinction at the Battle of Fontenoy (1745) and was later killed fighting for King George II against the Jacobites at the Battle of Falkirk (1746).

However, that account has been disputed by several genealogists, who instead maintain that Anne was the daughter of one Andrew Munro, Sheriff Clerk for Moray during the Restoration, who actually got into trouble with the law for refusing to recognize the legitimacy of the Stuart King James II. But regardless of which account is the truth, it is unquestionable that Hugh was born to a staunchly Presbyterian, Whiggish family.

Hugh’s ambition was to be a medical doctor, and to that end he enrolled in the University of Edinburgh at the age of 15 to study medicine. In 1744, at the age of 19, Hugh graduated as a full-fledged physician, and began to practice medicine independently. However, no sooner had he begun his career when events unfolded that would turn young Hugh’s world upside down.

The ‘45

These events revolved around the Jacobite Uprising of 1745. Ever since 1688, when the Catholic King James II had been deposed by his Protestant son-in-law (William of Orange – soon to be King William III), there had been a fairly significant faction supporting James’ restoration to the throne, largely centered among the Catholic Highlanders and the Irish. These loyalists to the House of Stuart were known as Jacobites, after the Latinization of the name James: Jacobus.

Both James and his son (Charles Edward Stuart, known as “The Old Pretender”) tried to raise revolts in Great Britain and Ireland to restore their family to the throne. James’ army, however, was shattered at the Battle of the Boyne (1690), while The Old Pretender’s attempt to raise a Scottish rebellion in 1715 similarly came to naught.

On August 19, 1745, the standard of revolt was raised by a new generation. The young and dashing Charles Edward Stuart, son of The Old Pretender and therefore known as The Young Pretender, landed in the Scottish Highlands to press his father’s claim to the Crown. He summoned all the clans to Glenfinnan, and thus began the last great romantic fling of the Highlands – the ’45.

Rather shockingly, Hugh Mercer chose to join the Jacobite Army as a medic. This was an astonishing decision, and quite frankly difficult to understand even today. Everything about Hugh Mercer suggested that he should be in vigorous opposition to the Jacobites. For starters, he was a Presbyterian, the son of a minister, and as a general rule the Presbyterians were the most staunchly opposed to the Jacobite movement and its “Popery”.

And when we examine his lineage on his mother’s side, his decision to join the Jacobites becomes even more baffling. Regardless of which of the two options we take regarding his maternal grandfather, he was either a military officer actively engaged in fighting the Jacobites (and indeed, killed in action at the Battle of Falkirk), or else he was a clerk who had gone through great hardship and persecution to resist the Stuarts back when they were on the throne. Either way, there can be no doubt that the Mercer family was staunchly opposed to Catholicism and the Jacobite cause. One can only assume that Hugh’s involvement in the ’45 created tremendous acrimony and most likely severed his relations with the rest of the family.

In any event, Hugh Mercer was present at the Battle of Culloden (April 16,1646), when the Jacobite hopes were firmly and decisively shattered. Wave after wave of clansmen, the cream of the Highland’s crop, rushed the British lines, where they were cut down by musketry volleys, cannister shot, and the bayonet. By the end of the day, some 2,000 Jacobites lay dead on the field of battle, their army and cause completely crushed. Bonnie Prince Charlie himself fled Scotland, never to return, and spent the remainder of his life on the Continent seeking solace in the bottle, a bitter and defeated man.

The British Army, commanded by King George II’s son, the Duke of Cumberland, proceeded to ravage the Highlands – massacring, looting, and raping, all in the name of restoring order. Ordinary men, women, and children were slaughtered by the victorious royal forces, without regard to sex, age, or condition. Hundreds of common rebels were hanged, banished, or transported to penal colonies overseas. The Highlander way of life was thoroughly repressed, never to rise again.

In the midst of all this was young Hugh Mercer. He was a young Presbyterian adrift, cut off from his family and people, living life on the run. There was no more future for him in Great Britain, and in the fall of 1746 he boarded a ship at Leith and made his way over to America.


Mercer arrived in Pennsylvania after his ocean crossing, but city life didn’t suit our Scotsman very well. After but a few weeks, Mercer moved into the colony’s undeveloped interior, settling in the Cumberland Valley, near what is now the borough of Mercersburg. There he returned to the medical profession, plying his services to the frontiersmen in the surrounding region.

Shortly after the French and Indian War broke out in 1755, Hugh Mercer joined the Pennsylvania State Militia, once again as a medic. He was commissioned as a captain in early 1756, and later in that year accompanied Lieutenant-Colonel John Armstrong on a raid deep in enemy territory.

The target was the Delaware village of Kittanning, which had been involved in several raids on the West Pennsylvanian frontier, and its chief, Captain Jacobs. Tactically, the raid was a success, and the colonists succeeded in destroying the village and killing Captain Joseph, but the militia also incurred significant numbers of killed and wounded.

Among those wounded was Hugh Mercer, who had been left behind as the raiding party withdrew. That put him in a very perilous situation, to say the least, as he was now alone and wounded, 90 miles away as the crow flies from the nearest friendly base, Fort Shirley. The Delaware, for their part, were now on the warpath, and they were hunting for stragglers to torture to death. Mercer, however, did the impossible, and he made the 14-day trek through nearly 100 miles of untracked forest, all while suffering from his injuries, evading capture by prowling Indians, and sustaining himself on grasses and herbs.

According to one biographer of his life, Mercer was actually on one occasion pursued by a group of Indians, but he managed to find a hollow tree trunk in which to hide. As he stood there, the Indians who were tracking him paused to take a rest around the very tree he was hiding in. This story may or may not be true, but regardless of its veracity, Mercer’s feat was an astonishing one, and he was promoted to colonel in recognition of it.

Mercer subsequently took part in the British capture of Fort Duquesne in 1758 and was subsequently placed in command of the new British fort constructed in its place, Fort Pitt. This was, to the best of my knowledge, the last action Mercer saw in the French and Indian War.


As the war wound down, Mercer was persuaded by several of his Virginian friends (including Brigadier-General George Washington) to move down to Fredericksburg, Virginia, where there was a significant Scottish community (one prominent Scot who later emigrated to Fredericksburg was John Paul Jones, later to become the “Father of the US Navy”).

While in Fredericksburg, Mercer made associates among the Virginia aristocracy, and when tensions with the mother country boiled over in the early 1770s, Mercer was a staunch member of the Patriot cause. As royal authority within the colonies broke down, Mercer found himself among the leaders of the emerging new order. He served on both Fredericksburg and Spotsylvania County’s Committee of Safety, which took over the Royal Governor’s executive powers to maintain the peace as the Revolution drew closer.

Mercer seems to have been a relatively early proponent of armed resistance of the Crown, and in the aftermath of the clashes at Lexington and Concord, when Virginia’s House of Burgesses voted to raise three regiments of militia, Hugh Mercer submitted his candidacy for command of one of the regiments. “Hugh Mercer”, his declaration read, “will serve his adopted country and the cause of Liberty in any rank or station to which he may be assigned”.

Mercer’s strong dedication to the principles of the Revolution fit in very well indeed with his Scottish Presbyterian background, but rather ironically, seems to stand out with regards to his former Jacobite comrades. Most of them seemed to have backed the Crown this time around (perhaps due to their Catholicism; or perhaps due to their trauma after the savagery meted out on them after their last rebellion). But regardless, the young Jacobite rebel from Aberdeenshire now found himself – thirty years later – once again in rebellion the Hanoverian dynasty.

In any event, Mercer was elected to the colonelcy of Virginia’s Third Regiment of Militia, and under its flag, marched away from his wife and children – whom he would never see again. Once encamped with his men, Mercer drilled them tirelessly and effectively, working to convert these farmhands and shopkeepers into soldiers capable of standing up to His Majesty’s armed forces. But he was not to remain in command of the Third Regiment for long, because on June 6, 1776, the Continental Congress in Philadelphia wrote to Mercer, promoting him to the rank of Brigadier-General in the Continental Army, and instructing him to report as soon as possible to headquarters in New York.

New York

Following the British evacuation of Boston on March 17, 1776, the Patriots waited with bated breath for the British counterattack. It was certain that the British target would be New York, and indeed, on July 3 the British made an unopposed landing on Staten Island. Washington had the unenviable task of trying to figure out how to defend Long Island, Manhattan, and the Jersey Palisades from being taken by the British. Washington was desperately trying to defend every point of landing, which ultimately meant that he was unable to adequately defend any of them.

This was the predicament in which Brigadier-General Mercer found his friend, George Washington, when he arrived in New York. Washington soon ordered him to take a large detachment of Pennsylvania and to construct a fort on the New Jersey side of the Hudson River, directly opposite Fort Washington in Manhattan. This fort, in tandem with Fort Washington, was intended to protect the Hudson from British warships, however, on the one occasion that British warships actually exchanged fire with the forts, it was a fiasco on the America side – several gunnery teams ran away at the first British broadside, while another failed to swab down their gun, which exploded and killed several of its crew.

In any event, Mercer’s position on the New Jersey side of the Hudson meant that he and his men were not involved in the catastrophes that befell George Washington’s army in Long Island and Manhattan, where the British took the islands with relative ease, suffering relatively minor losses compared to the Americans, who lost somewhere about 5,000 men to death, injury, or capture.

Once Fort Washington on the Manhattan side of the Hudson was lost, Fort Lee no longer served an effective purpose. Accordingly, when the British succeeded in bypassing General Nathanael Greene’s pickets, and making an unopposed nighttime crossing of the Hudson just a few miles north of Fort Lee, Washington ordered all of his men to make a full and complete withdrawal from the banks of the Hudson. And so it was, that the long and dismal retreat through New Jersey began.

Crisis of the Revolution

By early December, when Washington had settled into winter quarters on the Pennsylvania side of the Delaware River, the Revolution seemed to be gasping its last breaths. Over the past several months, the Americans had been defeated repeatedly, with nary a victory to raise their spirits. Washington was down to less than 4,000 effective fighting men. Morale was at an all-time low, and what was worse, a large percentage of the militias’ terms were set to expire by the end of the year, including some of Washington’s best and most experienced fighters.

Everything was in short supply: money, food, shelter, clothing, ammunition – the Continental Army was so ragged that when Washington made his famous crossing of the Delaware on Christmas Eve, Major James Wilkinson recorded that the moving army left behind a trail of blood on the snowy ground, from all the soldiers who were either going barefoot or with tattered shoes. It seemed as though the Revolution was at an end.

This was the atmosphere in which Thomas Paine wrote his celebrated The American Crisis, exhorting the rebels to persevere despite the tremendous adversities which had befallen the patriot cause: “These are the times that try men’s souls. The summer soldier and the sunshine patriot will, in this crisis, shrink from the service of their country; but he that stands it now, deserves the love and thanks of man and woman. Tyranny, like hell, is not easily conquered; yet we have this consolation with us, that the harder the conflict, the more glorious the triumph.”

And glorious, indeed, was to be the triumph that Washington and his trusted subordinates – among whom we can count Hugh Mercer – would soon achieve.

The Battles of Trenton and Assunpink Creek

In these darkest moments of the Revolution, Washington decided on wagering all on one last great fling – a surprise attack on one of the Hessian garrisons occupying New Jersey. General Howe, confident that had pacified New Jersey and Washington’s army no longer posed a significant threat, had spread his forces thin, occupying a string of garrisons across the colony.

This enabled George Washington to execute his most famous exploit, when he crossed the Delaware River with some 2,400 men on the stormy night of Christmas 1776, catching the Hessians by surprise in Trenton and utterly smashing them, taking over 1,000 prisoners. This coup-de-main has been traditionally remembered as Washington’s finest exploit.

However, Major John Armstrong Jr., Hugh Mercer’s aide-de-camp and later Senator for New York, has maintained that it was Hugh Mercer who had initially raised the idea of a strike at Trenton to Washington, and as such our doughty Scotsman gains a great deal of the credit for the stunning colonial victory, which reinvigorated patriotic enthusiasm all across the colonies. Of course, it is entirely possible that Armstrong was misrepresenting the facts, but regardless of the veracity of Armstrong’s claim, it is indisputable that Hugh Mercer was given a prominent voice in the drafting of the plans leading up to the attack, and was one of Washington’s most trusted subordinates.

But as marvelous a victory as Trenton was, it was only the first blow, and the British retaliation was sure to arrive. Lieutenant-General Charles Cornwallis, who was quite literally on board the HMS Bristol and about to set sail for England, had his leave abruptly cancelled upon the news of the disaster at Trenton, and was tasked with the complete destruction of Washington’s army.

The rather disgruntled Cornwallis arrived in Princeton on New Years Day, 1777. He had assembled a large British force, some 8,000 strong, which included some of the best battalions deployed in America. Not one for subtlety, Cornwallis was determined to overwhelm Washington’s ragged army with overwhelming force, by way of a direct frontal assault.

Washington, for his part, chose to make his stand on good defensive ground behind Assunpink Creek, to the southeast of Trenton. This was a strategy which had worked numerous times in the past, most famously at Bunker Hill – persuade the British to launch a direct frontal attack against a good defensive rebel position.

On January 2, Cornwallis and his men set out on the approximately 10-mile-long march from Princeton to Trenton, with the aim of striking Washington’s army. Some 1,500 men were left behind in Princeton, under the command of Lieutenant-Colonel Charles Mawhood, with the instructions not to join Cornwallis’ force at Trenton until the next morning. Cornwallis hoped to engage with Washington on that same day, but Washington sent out several units of militia and crack riflemen, under the command of Colonel Edward Hand, to harass the British all along their march. This they did successfully, delaying the British advance for as long as was possible in the face of superior numbers and training.

By the time the British reached Trenton, it was nearly dusk. Washington had withdrawn all of his troops to behind the Assunpink Creek, and focused all of his musketry and artillery on the creek’s fords, hoping to prevent the British from crossing the creek. The British made three probing assaults across the bridge, but they were each thrown back with substantial casualties. As night gathered, Cornwallis decided to call of his attack and wait until morning, at which time he would eradicate Washington’s army. Cornwallis’ words as he took leave of his officers were, “We’ve got the old fox safe now. We’ll go over and bag him in the morning.”


But the Old Fox had no intention of being “bagged”. He was fully cognizant of the fact that his army, largely comprised of undisciplined militia units, could hardly stand against the crack British and Hessian regulars facing them, and that a determined foe could cross the fords which had hitherto kept the British away. So, standing and fighting wasn’t an option. But neither was retreat. The Continentals had the ice-choked Delaware River to their backs – there was no way they were going to be able to cross that before morning.

Accordingly, Washington held a council of war with his subordinates in the quarters of General Arthur St Clair, who suggested that they flank the British force by way of a night march and hit their lightly defended rear at Princeton, with all of its baggage and supplies. Hugh Mercer is recorded as having immediately fallen in with this idea, and he forcefully advocated it to the other more reluctant members of the council. Finally, all of the attendees agreed on the plan, and by 2 AM, the bulk of Washington’s army was on the march once again, leaving only 500 men behind to keep the fires lit and make noise, so that the British wouldn’t suspect that the old fox was on the move.

The Continentals marched through the night, and in the early light of the morning of January 3rd, they spotted Mawhood’s men marching to reinforce Cornwallis at Trenton. Mawhood, however, spotted the Americans as well, and he immediately turned his army about and began marching back to Princeton.

The American vanguard, under the command of Hugh Mercer, first made contact with Mawhood in an apple orchard. The two sides exchanged several musket volleys with each other, but after three volleys Mawhood gave the order to his British regulars to charge the Americans with the bayonet.

Bayonet charges were always an extremely effective tactic, even against numerically superior foes. In this case, it was even more effective, as Mawhood held a substantial numerical advantage over Mercer’s men. Mercer’s men didn’t stand a chance, and they broke and fled as the British charged. Mercer, however, attempted to rally his men to stand and fight the charging redcoats, but his horse was shot out from under him, and Mercer fell to the ground.

He was immediately clubbed on the head by the butt of a British musket and fell to the ground. When he rose, he was surrounded by a group of redcoats, who apparently believed they were surrounding Washington himself. “Call for quarters, you damned rebel”, shouted the British soldiers, but Mercer defiantly replied, “I am no rebel” and slashed at them with his saber. At that, the British soldiers knocked him down again, and began clubbing him on the head and bayonetted him seven times, until one of the redcoats yelled “Damn him he is dead! Let us leave him.”

At this moment Washington came on to the field with the rest of his men. With his characteristic calmness in the face of adversity, he succeeded in rallying Mercer’s broken men and returning them to the field. Washington eventually carried the day, winning his third victory over the British in ten days, but as he told the Continental Congress in his official dispatch, “This piece of good fortune is counterbalanced by the loss of the brave and worthy General Mercer.”

Although Hugh Mercer hadn’t been killed on the spot, as the redcoats believed, his wounds were mortal. According to legend, when the Americans retook the field and found him lying there, they naturally insisted upon taking him behind the lines. Mercer, however, refused, and insisted on watching the remainder of the battle propped up against a nearby oak tree. This oak tree, known as the Mercer Oak, was preserved until 2,000, when it was uprooted by a storm. The Mercer Oak is prominently displayed on the seal of Mercer County (the county in which Trenton and Princeton are located).

After the battle had been won, he was moved to the Clarke House, where he was attended to by his close friend, the famous patriot Dr. Benjamin Rush. Mercer lingered on in agony for nine days after the battle, until he finally passed away on January 12, 1777, just four days shy of his 51st birthday. He was one of Washington’s best commanders, cut down in battle while serving in the cause of liberty.

As an epitaph to General Mercer, I leave here the words he spoke regarding the Revolution for which he gave his life: “We are not engaged in a war of ambition, or I should not have been here. Every man should be content to serve in that station in which he can be most useful. For my part, I have but one object in view, and that is, the success of the cause ; and God can witness how cheerfully I would lay down my life to secure it.” May his memory be an inspiration to all patriots to continue to sacrifice what they must for our precious freedoms.


Sources used:

David Hackett-Fisher, Washington’s Crossing. New York: Oxford University Press (2004)

John T. Goolrick, The Life of General Hugh Mercer. New York: The Neale Publishing Company (1906)

Christopher Ward, The War of the Revolution. New York: Skyhorse Publishing (2011)


Leave a Reply