Fort William Henry was constructed on the southern end of Lake George by the British during the French & Indian War - the American colonial extension of the global Seven Years' War. The construction of the fort prompted a series of skirmishes with the French in 1755, referred to collectively as the Battle of Lake George. Although there were significant casualties on both sides, the British claimed victory and Fort William Henry was completed. Only two years later, though, Fort William Henry would be seized by the French and the British would be forced to retreat.
The Siege
The Lake George area was a hive of activity during the French & Indian War. French troops retained a presence around the lake and constructed Fort Carillon (later named Fort Ticonderoga) on the northern end of the lake soon after Fort William Henry was completed. French General Louis-Joseph de Montcalm began planning an advance against Fort William Henry and recruited both French troops and Native American allies. British Lieutenant Colonel George Monro took command of Fort William Henry in the spring of 1757.
At the end of July in 1757 French troops led by François de Gaston (Chevalier de Lévis) and Montcalm, as well as their allies, travelled over land and water to Fort William Henry, camping nearer and nearer to the British fort. On August 3, skirmishes broke out and the French blockaded the road that led to the nearby British Fort Edward. Monro rejected Montcalm's first offer of surrender and requested reinforcements from General Daniel Webb at Fort Edward. Webb wrote back a refusal to send any men the 16 miles to Fort William Henry and stated that Monro should negotiate terms for surrender - a message which was intercepted by the French and given to Montcalm.
With this knowledge, Montcalm began siege operations, firing at the fort and moving steadily closer to the fort's walls. This six-day attack by Montcalm and his 8,000 French troops, Native allies, and Canadian volunteers left Fort William Henry near collapse. The fort's walls were breached, its guns were overused, and the British has sustained many casualties, leading Monro to surrender on August 9.
Montcalm's terms of surrender allowed for the British and their camp followers to retreat to Fort Edward under French escort, based on the condition that the troops would not engage in fighting for 18 months. The British would retain the full honors of war, and were allowed to keep their personal belongings as well as a single symbolic canon. The ill and wounded would be cared for by the French and released when their health improved. As the British retreated on August 10, they - and the people left behind - were attacked by the French's Native Americans allies, possibly due to miscommunication among the diverse languages or because the Native Americans felt that they had not received the war trophies they were promised. The weaponless British received varying amounts of French aid during the attacks.
The collective deaths of the British following the surrender of Fort William Henry are remembered today as a "massacre". There still remains much speculation as to how many people (including women, children, and slaves who were not part of military records) were killed, with reports varying from a few dozen to over one thousand deaths. The massacre was later dramatized in James Fenimore Cooper's book, The Last of the Mohicans, and its numerous film adaptations.
Sources:
http://www.fwhmuseum.com/history.html
http://www.militaryheritage.com/wm_henry.htm
The Battle of Fort Duquesne a British assault on the eponymous French fort (later the site of Pittsburgh) that was repulsed with heavy losses on 14 September 1758, during the French and Indian War.
The attack on Fort Duquesne was part of a large-scale British expedition with 6,000 troops led by General John Forbes to drive the French out of the contested Ohio Country (the upper Ohio River Valley) and clear the way for an invasion of Canada. Forbes ordered Major James Grant of the 1st Highland Regiment to reconnoiter the area with 850 men. When Grant proceeded to attack the French position, his force was out maneuvered, surrounded, and largely destroyed by the French and their native allies led by François-Marie Le Marchand de Lignery. Major Grant was taken prisoner and the British survivors retreated fitfully to Fort Ligonier.
After repulsing this advance party the French, deserted by some of their native allies and vastly outnumbered by the approaching Forbes, blew up their magazines and burnt Fort Duquesne. In November the French withdrew from the Ohio Valley and British colonists erected Fort Pitt on the site.
Forbes commanded between 5,000 and 7,000 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. Bouquet sanctioned a reconnaissance of Fort Duquesne by Major James Grant of Ballindalloch,
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