Fresh from undoing Herkimer's ugly plot, Brant abandoned the Susquehanna and went off in the direction of Lake Ontario. A great Indian council was to be held at Oswego, and possibly he was hurrying to this meeting.
A vigorous campaign had been set on foot for the midsummer of 1777 by General Burgoyne, who was now in command of the British forces at Montreal. It was arranged that Burgoyne should strike southward with the main army until he reached the Hudson river. Meanwhile another body of troops, under Lieutenant-Colonel St Leger, would make a long detour by way of Lake Ontario and the western part of the colony of New York. The object of this latter movement was to rally the Indians, collect a force of loyalists, and fight through the heart of the country with the hope of forming a junction with Burgoyne's army at Albany.
St Leger reached Oswego about the middle of July. There he was joined by a regiment of loyalists, the famous Royal Greens, and a company of Tory Rangers under Colonel John Butler. Brant was present with two hundred Mohawks, while a large band of Senecas were also grouped under the king's standard. In all there were seventeen hundred men, fully one thousand of whom were Indians under the supreme command of Captain Brant.
On starting out, St Leger, who knew that a surprise might be attempted, outlined his order of march with great care. A detachment from one of the battalions was sent on ahead, and this was later joined by Captain Brant with a party of his warriors. Five columns of Indians went in front, in single file; the flanks also were protected by Indians at a distance of one hundred paces from the central column.
It was intended that the first blow should be struck at Fort Stanwix, on the head-waters of the Mohawk. This was an old English stronghold that had fallen into decay, but was being repaired and defended in the interest of the revolting colonies by Colonel Peter Gansevoort. It lay on the traffic-road to Oneida Lake, and was considered a strong point of vantage. Its garrison was made up of about seven hundred and fifty colonials. They had provisions enough to last for six weeks and a goodly supply of ammunition, and hoped to be able to withstand attack until help should arrive.
The English leader reached this fort on August 3, and immediately began to invest it. A demand was sent in under a flag of truce calling upon the garrison to surrender. St Leger said it was his desire 'to spare when possible' and only 'to strike where necessary.' He was willing to buy their stock of provisions and grant security to all within the fort. The offer was generous, but the garrison rejected it with a good-tempered disdain and the siege went on with renewed earnestness. The Indians, hiding in the thickets, poured their fire upon those who were working on the walls. The presence of the savages lent a weird fury to the scene, made it, indeed, well-nigh uncanny. One evening in particular they 'spread themselves through the woods, completely encircling the Fort, and commenced a terrible yelling, which was continued at intervals the greater part of the night.' Fort Stanwix was soon in dire straits. The news of the investment had sent a thrill through the whole of the Mohawk valley. The colonials came together in haste, and soon about a thousand of them, led by Nicholas Herkimer, were ascending the river in straggling array. They hurried on their course with such zeal that they did not even send out scouting parties to warn them of danger and prevent surprise. On August 5 this relief force was close to Oriskany, and only eight miles distant from St Leger's position. Herkimer now matured a clever plan, the success of which he confidently expected would bring him victory. He chose three men and sent them forward to gain entrance to the fort and to tell Gansevoort that help was coming. The moment they arrived the besieged were to fire three guns in rapid succession. This was to be Herkimer's signal; he would speed at once along the road to the British position and fling himself on its rear, while, at the same time, Gansevoort must issue forth and attack it in front. St Leger's army, it was hoped, would crumble in hopeless defeat between two shattering fires.
As fortune would have it, this ruse was doomed to complete failure. The messengers set out at eleven o'clock at night, and Herkimer thought they would surely reach the fort by three in the morning. But he waited in vain the whole night through; no sound of cannonade disturbed the quiet air. As the hours crept by his officers became fretful and impatient; in the end they declared for an immediate advance, denouncing Herkimer as a faltering coward. At length the old man, sorely against his will, gave the order to march. The relief party streamed through the forest with disordered ranks. In the meantime Brant's Indians had not been idle. They had carefully watched the manoeuvres of the hostile force, and had given timely warning. St Leger at once took steps to bar the road to attack. For this purpose a division of the Royal Greens was detailed, as well as the Tory Rangers, with Butler in command. The bulk of the contingent, however, were Indians, and it fell to the lot of Joseph Brant to fasten Herkimer in the strong meshes of his net.
The ground over which the Americans had to pass was uneven, and this had not escaped the watchful eye of Brant. He was an adept in the tactics of Indian warfare, and now used his knowledge to good effect. Herkimer had not gone far along the narrow trail before he found himself in difficulties. The road slanted down into a boggy hollow some six or seven miles below Fort Stanwix. This hollow had a winding course in the form of a crescent, and across its march a causeway of heavy logs had been built. Between the ends of the encircling ravine there was an elevated position, thickly wooded and dry. Upon this Brant had laid his ambush, having posted his men with only a slight opening in their ranks towards the incline of the road.
Down into the gully came the colonials, their wagons and a small guard bringing up the rear. As they toiled up the opposing ascent, the gap was closed upon them, and they were surrounded on every side. The rear-guard were left behind with the wagons and fled in a tumult, with a throng of Indians in close pursuit. From the sheltering trees a deadly fusillade swept the hapless files of those who were hemmed about on the rising ground. Darting from their cover, the Indians sprang upon such as lay wounded and dispatched them with knife and tomahawk.
The first onslaught had resulted in a carnival of blood. Now the colonials, owing to their numbers, were able to get together and to place themselves on the defensive. The fight soon became hand to hand and there ensued one of the most gruesome melees of the whole War of the Revolution. The men were able to look into one another's faces; they fought at quarters too close for bullets, and relied upon gun-stock, knife-blade, and bayonet. There was slashing and cutting, clubbing and throttling, and often in their frenzy they grappled tight and died in one another's fast embrace. In the midst of it all Herkimer proved himself no craven. With his leg ripped by a bullet he propped himself against a tree, lit his pipe, and directed the order of the battle. Above the din rang out clear the wild cries of the red men, their painted bodies flashing bright among the trees. In the forefront was Brant, fighting vehemently, his towering form set firmly, his deep voice echoing loud.