The Forbes Expedition was a British military expedition led by Brigadier-General John Forbes in 1758, during the French and Indian War. Its objective was the capture of Fort Duquesne, a French fort constructed at the confluence of the Allegheny and Monongahela Rivers (in present-day Pittsburgh, Pennsylvania) in 1754.
Forbes commanded between 6,000 and 8,000 men, including a contingent of Virginians led by George Washington. Forbes, very ill, did not keep up with the advance of his army, but entrusted it to his second in command, Lt. Col. Henry Bouquet, a Swiss officer commanding a battalion of the Royal American Regiment.
The expedition methodically constructed a road across what is now southern Pennsylvania, but was then largely Indian territory. This was in contrast to a similar expedition led by Edward Braddock in 1755 that ended in disaster. Working for most of the summer on the construction of the road, fortifications, and supply depots, the expedition did not come within striking distance of Fort Duquesne until September 1758. In mid-September, a reconnaissance force was soundly defeated when its leader, Major James Grant, attempted to capture the fort instead. The French, their supply line from Montreal cut by other British actions, attacked one of the expedition's forward outposts, Fort Ligonier, in an attempt to either drive off the British or acquire further supplies, but were repulsed.
The Treaty of Easton concluded on October 26, 1758, caused the Lenape and Shawnee tribes in the Ohio Valley to abandon the French. This collapse of Native American support made it impossible for the French to hold Fort Duquesne and the Ohio Valley. When the expedition neared to within a few miles of Fort Duquesne in mid-November, the French abandoned and blew up the fort. Three units of scouts led by Captain Hugh Waddell entered the smoking remnants of the fort under the orders of Colonel George Washington on November 24. General Forbes, who was ill with dysentery for much of the expedition, only briefly visited the ruins. He was returned to Philadelphia in a litter, and died not long afterward.
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- Forbes Expedition (George Washington's Mount Vernon)