The Siege of Fort Stanwix, American Revolution. 1777. Where an Insurrection Turn into a Revolution.

Britain’s failure to seize Fort Stanwix played a critical role in the collapse of their strategy to divide the colonies. Without control of the fort, they were unable to secure the Hudson River corridor or dominate central New York, objectives that had been essential to cutting the American rebellion in half. That one position, held against the odds, helped fracture the campaign designed to isolate New England and strangle the revolution in its infancy.

Fort Stanwix. August 3 - 22, 1777.
American Forces: ~ 800 Militia Men.
British and Allied Forces: 875 Soldiers and 800 to 1,000 Mohawk Warriors.

Additional Reading and Episode Research:

• Pancake, John. 1777, the Year of the Hangman.
• Ward, Christopher. The War of the Revolution.
• Nickerson, Hoffman. The Turning Point of the Revolution.

Transcript

Thanks for tuning into this episode of History's Greatest Battles, season two, where we explore history's greatest sieges. If you know somebody that enjoys this genre of history, please share the podcast with them... and give us a review.

In the summer of 1777, the British Empire launched a coordinated military campaign intended to split the American colonies in two. The objective was strategic and clear: isolate New England, the most ideologically aggressive region of the rebellion, from the southern and middle colonies where British authority still held firmer ground. If the colonies could be divided, they could be conquered in sections. The campaign was complex, involving multiple columns converging on the Hudson River corridor, one pushing down from Canada, another striking east from Lake Ontario, and a third expected to move north from New York City.

This plan had been drawn in London, and it carried the weight of imperial assumption: that trained soldiers, traditional discipline, and overwhelming force would suffice to bring rebellious provincials back under the Crown. It was a plan crafted with confidence, and it began with apparent success. British General John Burgoyne moved swiftly out of Canada, capturing Fort Ticonderoga with ease. Further west, another British column was sent to seize control of the Mohawk Valley, a critical corridor of communication and supply.

What followed was a failure that did not look significant at the time. A remote American position, not central to the campaign’s immediate goal, managed to hold longer than it should have. But that delay, compounded by logistical strain and a sudden collapse in native support, derailed one arm of the British offensive. That alone would not have changed the war. What made it decisive was timing. While one British general waited for help that would never come, the American forces facing him gathered strength. When the confrontation came weeks later near the village of Saratoga, it was not the divided colonies that broke apart, it was the British line.

The consequences were global. France, watching for a credible rebel victory, interpreted the British failure as proof that the American effort had staying power. Within months, they recognized American independence and entered the war, not with token support, but with armies, fleets, and the resources of a European power. That intervention expanded the war beyond North America, forced the British to divide their military focus across continents, and ultimately transformed a colonial insurrection into a legitimate war for independence.

This episode examines the position that held. It was not a battlefield crowned in glory. It was a siege, fought in silence, with no certainty of survival. Its victory was measured not in ground taken, but in time stolen. And that time reshaped the outcome of the American Revolution.

Let’s no experience, the Siege of Fort Stanwix.
 Welcome to History's Greatest Battles, Season 02, episode 39: The Siege of Fort Stanwix, during the American Revolution.

From the third through the 22nd of August, 1777.

American Forces: roughly 800 men.

British Forces: 875 British and Allied forces with an additional 800 to 1000 Indians.

Britain’s failure to seize Fort Stanwix played a critical role in the collapse of their strategy to divide the colonies. Without control of the fort, they were unable to secure the Hudson River corridor or dominate central New York, objectives that had been essential to cutting the American rebellion in half. That one position, held against the odds, helped fracture the campaign designed to isolate New England and strangle the revolution in its infancy.

By late summer of 1776, the American Revolution stood on the edge of collapse. General Sir William Howe, leading Britain’s professional war machine, had seized New York City and locked down the surrounding territory. The British flag flew over America’s most important port, and the rebels were reeling.

Then, in the dead of winter, George Washington did the unthinkable. With frost biting at his heels and morale bleeding out, he struck hard, first at Trenton, then at Princeton, hammering British positions with sudden, devastating blows. He didn’t just win battles; he resurrected the fight.

By spring, Washington’s daring had lit a fire. Men who once doubted the cause now marched to join it. His victories had turned despair into momentum, and the ranks began to swell.

While the snow settled over New York City, Howe sat with his staff, planning the next strike. His eyes were on Philadelphia, the seat of the Continental Congress, the nerve center of rebellion. Take that city, and the revolution would lose its head.

Howe’s plan was bold. He’d load 20,000 men onto ships, sail them down the coast, then push them up through the Chesapeake. From there, they’d drive straight toward Philadelphia, approaching from the southwest like a hammer swinging in from the flank.

But north of the border, another British general was drawing up plans of his own. Sir John Burgoyne, sharp and confident, was about to launch the most ambitious campaign of the war.

Burgoyne saw the map for what it was, a battlefield of choke points and lifelines. If he could carve through New York, he’d split the colonies in two, cutting New England off from its southern allies. So, he drafted a triple strike straight into the heart of the state.

His own column, 8,000 strong, would march south out of Canada, slicing down Lake Champlain, heading for Albany. If successful, he’d lock down the northern corridor.

Meanwhile, a smaller force, 850 Europeans, would push by water, riding the St. Lawrence, crossing into Lake Ontario, and cutting east through the Mohawk Valley to meet him at Albany.

And to finish the job, he needed Howe to drive north from New York City, securing the Hudson River Valley and sealing the trap shut.

But the British command was fractured. Howe had his sights locked on Philadelphia, not Albany. He’d promised to support Burgoyne later, but promises don’t win campaigns, and when the time came, Howe was nowhere near.

In the early summer of ’77, Burgoyne made his move. His forces surged out of Canada and swept through Fort Ticonderoga without breaking stride. The bottom of Lake Champlain was his.

But the pace soon faltered. The wilderness of upstate New York isn’t forgiving, and to keep his supply lines alive, Burgoyne’s men had to carve a road through dense, untamed forest. Progress turned from conquest to labor.

While Burgoyne hacked his way south, another prong of the British assault was already in motion. Brevet Brigadier General Barry St. Leger was leading a composite force, 850 men made up of British regulars, German auxiliaries, and hardened American loyalists, sailing up the St. Lawrence toward Lake Ontario.

By July 25th, they reached Oswego, New York. There, they linked up with between 800 and 1,000 Mohawk warriors, led by the formidable Joseph Brant, an ally as fierce as any the British could ask for.

The Mohawks came from the Iroquois Confederacy, a powerful league of six nations that had long fought beside British redcoats in brutal frontier wars against the French and their Algonquin allies.

But the Confederacy wasn’t united in this war. The Oneidas and Tuscaroras either stayed neutral or leaned toward the revolutionaries, splitting the once-iron alliance of the Iroquois.

St. Leger pushed west along a time-worn path of invasion. Wood Creek, starting at Oswego, snaked eastward toward the Mohawk River, a known artery of war from conflicts past.

But the waters don’t quite meet. There’s a break, a mile of rugged terrain where men had to drag their boats by hand across the land. That mile had long been a portage, a critical link in the chain.

Sitting squarely on that lifeline was Fort Stanwix, a British creation from 1758, hammered together in the days of the French and Indian War.

After the last war, the fort had rotted in the wilderness. But the rebels in western New York saw what it meant, they knew that whoever held Stanwix held the gate to the Mohawk Valley.

So, in the spring of ‘77, local militia under Colonel Peter Gansevoort and Lieutenant Colonel Marinus Willet moved in. Their orders were clear: make Stanwix strong again.

They worked like men who knew what was coming. By early August, they had hauled the crumbling outpost back from the brink, just in time. Days later, St. Leger’s column appeared on the horizon.

Rebel prisoners had warned St. Leger that Fort Stanwix was bristling with defenders. But he dismissed the reports, scoffing at the numbers. He believed the place was barely held, sixty men at most. In reality, six hundred seasoned fighters stood behind those walls.

As his troops neared the fort, word came of a supply convoy heading in, laden with provisions and reinforcements. St. Leger reacted fast, sending rangers and Mohawk warriors to intercept it.

The enemy arrived on August 2nd, but too late. The convoy had slipped in under their noses, bringing with it two hundred more men and the supplies to dig in for a long fight.

The main British force rolled in the next day, planting its standard before the gates of Stanwix.

Certain he could intimidate the defenders into submission, St. Leger staged a grand display, marching his men in full force before the fort’s watchful eyes.

But the spectacle backfired. Nearly a thousand Mohawk warriors stood among the ranks, and the sight of them didn’t break the defenders’ will, it hardened it. These men had lived through generations of bloodshed on the frontier, and their hatred for Indian warfare ran deep.

St. Leger sent a formal demand to surrender. No reply came. The silence was his answer. With no other option, he ordered the siege to begin.

St. Leger arrived with grit, but not enough firepower. His artillery train was light, too light to batter Stanwix’s rebuilt walls. The fort could take a beating, and he couldn’t deliver one.

He moved to encircle it anyway, doing what he could with what he had. But the ground worked against him, thick woods, swampy stretches, terrain that broke lines and scattered formations. A full encirclement was out of the question.

So, he improvised. Outposts went up along the portage road. His main camp dug in to the north and east. The Mohawks, loyalists, and a detachment of British regulars set up south of the fort. It was a loose ring, but a ring nonetheless.

Knowing he couldn’t hold the line without better guns and steady supplies, St. Leger sent most of his men, alongside a cadre of rugged Canadian woodsmen, into the trees. Their task: carve a sixteen-mile road through unforgiving forest to bring up the gear he needed to win.

At the same time, he ordered Wood Creek cleared. The Americans had choked it with felled trees, turning it into a graveyard for boats. That blockade had to go.

That left only 250 men to maintain pressure on the fort while the rest hacked at the wilderness. It was enough to maintain the siege in name, but only just.

Then, on August 5th, word came from the Mohawks. A rebel force was on the move, marching out from Fort Dayton, thirty miles away and closing.

They were eight hundred strong, militia from the Mohawk Valley under Brigadier General Nicholas Herkimer, a local man, tough as they come, and ready for a fight.

Herkimer had set out the day before, on August 4th, with four hundred ox-carts packed with supplies. In two days, he pushed twenty-two miles through rough country, determined to reach Stanwix.

St. Leger didn’t have men to spare, but he had no choice. He peeled off a sliver of his force, some rangers and the bulk of Brant’s Mohawks, and sent them to intercept Herkimer in the wilderness.

Near a place called Oriskany, Herkimer’s column moved single-file through a tight mountain pass. That’s where the axe fell. The ambush was brutal.

But the strike came early. The Mohawks sprang the trap too soon. Herkimer’s men weren’t caught sleeping, they had just enough time to fight back.

As the woods roared with gunfire, a thunderstorm broke overhead. The downpour paused the bloodshed. Herkimer, wounded but still commanding, rallied his men to a hilltop and locked them into a tight defensive ring.

When the storm passed, the fight flared up again. But the patriots held firm, dug in, bleeding but unbroken. The Mohawks, frustrated by mounting losses, pulled back, leaving over 200 dead or wounded in the mud behind them.

The British regulars, outnumbered and exposed, fell back too. The ambush had turned into a grind, and they’d paid dearly for it.

While bullets flew at Oriskany, Herkimer’s riders reached Fort Stanwix. The garrison now knew help was coming, and they didn’t waste the moment.

Lieutenant Colonel Marinus Willet led 250 men out of the gates in a swift, ruthless sally. They struck the barely guarded Indian camp to the south, tore through it, looted everything they could carry, and vanished before the Mohawks got back.

The Mohawks had had enough. The failed ambush, the loss of their camp, it broke their appetite for the fight. They started voicing their anger, and loudly. The siege no longer looked like a victory to them.

St. Leger, watching his grip slip, grew desperate. His light cannons still couldn’t crack the walls. So, he ordered siege parallels, trenches and earthworks, to inch his guns closer to the fort’s throat.

Inside the fort, Colonel Gansevoort wasn’t sitting idle. Under cover of night, he sent runners through enemy lines, each one carrying a simple message to Fort Dayton: We’re holding, but we won’t hold forever.

General Philip Schuyler, already neck-deep managing Burgoyne’s push down the Hudson, now faced another front. His officers balked at the idea of diverting troops to Stanwix, thinking the Mohawk Valley wasn’t worth the risk. Schuyler knew better.

At last, Schuyler gave the order: Fort Stanwix would not be left to fall. Benedict Arnold, brilliant, aggressive, unpredictable, stepped forward. He wanted the mission. He got it.

With just 500 Continentals under his command, Arnold didn’t waste time with conventional strategy. He aimed to end the siege not with blood, but with fear, and he knew exactly how to do it.

Arnold grabbed a captured loyalist, half-crazed, unstable, the kind of man people listened to for all the wrong reasons, and sent him into the Mohawk camp with one story: that Arnold’s army wasn’t five hundred men. It was thousands, and it was coming fast.

Among the Mohawks, such madness wasn’t mocked, it was revered. They took his words as prophecy. The name Benedict Arnold carried weight, and the idea that he was thundering toward them with an unstoppable host shattered what resolve remained.

Arnold’s reputation alone was enough. The Mohawks didn’t wait to see the truth. They turned on the British, looted their supplies, clothing, liquor, whatever they could carry, and walked off the field.

With his native allies gone and his siege in ruins, St. Leger had no cards left to play. On August 22nd, he broke camp and marched his battered force back toward Canada, retreating the same way he had come, defeated, humiliated, and empty-handed.

St. Leger’s retreat wasn’t just a tactical failure, it was a death blow to Britain’s New York campaign, the very axis on which their grand strategy for the war was meant to turn.

By September, Burgoyne hit a wall near Saratoga. Rebel resistance stiffened, and he dug in, waiting for backup from either St. Leger or Howe. Neither came.

The British plan had crumbled. Burgoyne was stranded in hostile territory, no relief in sight. He was alone.

He tried one more time to reach Albany in October. It failed. Surrounded, outnumbered, and out of time, Burgoyne surrendered his entire army.

The surrender sent shockwaves. Just as Trenton and Princeton had reignited the revolution, Saratoga lit it into a blaze. And in Paris, it sealed the deal, the French now backed the Americans, throwing in ships, men, and guns.

The stand at Fort Stanwix didn’t just stop St. Leger, it strangled the British campaign at its root. That stubborn little garrison didn’t just defend a fort. They helped doom Burgoyne... and with him, the empire’s last real shot at crushing the revolution.

The garrison at Fort Stanwix wasn’t supposed to matter. A forgotten outpost in a backwater valley, manned by farmers in homespun and officers barely seasoned by war. But when the British came down from the north, wrapped in banners and arrogance, it was those men who held the line.

They held against siege, against starvation, against the brutal shadow of frontier warfare. They held when help was uncertain, when the sky itself seemed to collapse in thunder and rain. They fought not for conquest, but for something far harder to measure, for the belief that liberty belonged to those willing to stand alone.

Their defiance shattered a British campaign. Their stubbornness isolated Burgoyne. And their courage helped turn the tide of a global conflict.

Because of them, the British war plan disintegrated. Because of them, France crossed the ocean to make this rebellion a revolution. And because of them... an empire began to crumble.
 It was not at Saratoga that the British lost America… it was in the mud outside Fort Stanwix, where ordinary men refused to break.