After the humiliating defeat of Major Grant, September 14, 1758, when he disobeyed his orders and attacked the French and Indians at Fort Duquesne and was himself taken prisoner, the French, exulting over their unlooked-for victory, believed that a successful attack could now be made upon the main army of General John Forbes in camp at Loyalhanna. By this bold stroke, in which they would use their entire force, they could, in the discomfiture of the English, end all hostilities, as they had done in the fateful defeat of Braddock.
General Forbes was wiser than his predecessor, and better appreciated the talents and experience of Colonel George Washington, and did not fail to seek his counsel.
General Forbes had joined Colonel Henry Bouquet at Loyalhanna and determined to advance upon Fort Duquesne. Washington drew up the plan, illustrating the proper disposition of the troops in the line of march, so the English would not again be overwhelmed by a surprise attack.
At this moment the forces of the French and their Indian allies rushed through the woods toward Loyalhanna, dragging some light cannon with them. They reached their objective before the British army had moved. An attack was made and long sustained, but the English, under General Forbes, repulsed the French, who returned to Fort Duquesne.
The battle of Loyalhanna has never been given its proper place in history for it was a noteworthy affair, important in its consequences.
The French had beaten Braddock by the aid of their Indian allies, and they hoped to defeat Forbes in the same way, but Colonel Bouquet had adopted the provincial practice of fighting Indians, which was the means of bringing them to a realization of their inability to conquer the English, and they abandoned hopes of success and quit the French.
The strength of the French garrison in Fort Duquesne in September, 1758, was 4000 troops, but by October this number was reduced to less than 2000, including the Indians. On September 22, Christian Frederic Post, the noted Moravian missionary and friend of the English, who had visited the garrison, reported its strength as 1400, but added he believed “there would be full 3000 French and Indians, almost all Canadians, who would be ready to meet the army under Forbes.”
The militia of Louisiana and Illinois left the fort early in November and went home. The Indians of Detroit and the Wabash country would remain no longer, and, what was even worse, the supplies destined for Port Duquesne had been destroyed by Bradstreet at Fort Frontenac. Hence M. de Ligneris, the commandant, was compelled by prospective starvation to dismiss the greater part of his force, and await the approach of the English with those that remained.
The French had always depended on the aid of the Indians to hold this fort. But it was the custom of the Indians after a battle, whether successful or not, to go home.