Explain what happened to British General Edward Braddock and his soldiers when they marched into the Ohio River Valley in 1755.

General Edward Braddock was a British commander who led a major expedition during the French and Indian War (1754–1763), which was part of the larger Seven Years' War (1756–1763). In 1755, he attempted to capture the French Fort Duquesne (present-day Pittsburgh, Pennsylvania) in the Ohio River Valley, a strategic point for control of the interior of the continent.

On July 9, 1755, as Braddock and about 1,400 of his troops marched towards Fort Duquesne, they encountered a smaller force of French soldiers and their Native American allies in an ambush. This battle is often referred to as the Battle of the Monongahela.

The British troops were trained for traditional European warfare, which involved fighting in formal battle lines in open fields. However, they found themselves in the densely forested terrain of North America, which was unsuitable for their conventional tactics. The French and Native forces used guerrilla-style tactics, firing from behind trees and using the natural landscape to their advantage.

The British forces were unprepared for this type of warfare and suffered significant losses. General Braddock was mortally wounded during the battle and later died on July 13, 1755. The British were ultimately forced to retreat, and the battle was a devastating defeat, resulting in high casualties and the loss of valuable supplies and equipment.