The first battle of the American Revolution was fought on July 9, 1755

From Braddock At The Monongahela:

After an epic march of 43 days covering over 100 miles across the heart of the Appalachians, a mixed force of British regulars and colonial militia were closing in on Fort Duquense, a French stronghold at the confluence of the Allegheny and Monongahela Rivers.

This operation was part of an elaborate three-pronged offensive designed to secure the American frontier from French inspired Indian depredations and open the lands of the Ohio Valley to settlement.

Like so many disasters it looked great on paper.

A faction of Braddock’s staff was eager to close with the French before they could abandon their fortification and deprive the British force of a military victory. They had prevailed upon Braddock to designate a “flying column” built around the 44th Regiment of Foot and Virginia militia. It was that force which broke camp early on the morning of July 9 and pushed across the Monongahela and into military history.
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I think of the defeat of Edward Braddock’s flying column on the outskirts of present day Pittsburgh as the first battle of the American Revolution.
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The significance of Braddock’s defeat was that the regulars of the British army were shown to be vulnerable to a motley mix of troupes de marine, coeurs du bois, Canadian militia, and Indians. That this force was similar to the militias of the various colonies was not lost on contemporary pundits. That the British could not be relied upon to protect the colonies or prevail in conflict with the French was a fact also not lost on the colonists.

The author then explains that the most significant aspect of Monongahela was the friendships that developed.

The cast at Braddock’ defeat reads like a veritable Who’s Who of the first two years of the American Revolution.

He names (among others) Horatio Gates, Charles Lee, Thomas Gage, Adam Stephen and William Crawford (who were both friends of Washington), Thomas Walker (Jefferson's friend) and a 21 year old teamster named Daniel Boone.

In short, any study of the American Revolution which fails to consider the long personal history between so many significant participants is inadequate. The officer’s mess on the approach to Fort Duquense would have brought Washington, Lee, Gates, Stephen, and others into intimate contact for hours each day. This surely affected the relationship Washington had with Gates and Lee during the Revolution compounded by the knowledge that they were Regulars and he was a volunteer aide de camp.
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Braddock’s defeat also served to catapult Washington into the first rank of colonial personages even though he was only 23 years old. He had achieved fame throughout the colonies for his expedition with Christopher Gist to carry a demand that the French evacuate the Ohio Valley. He achieved international notoriety for his conduct at Jumonville Glen and Fort Necessity. The French labeled him a cold blooded killer after the Iroquois chieftain Tanacharison tomahawked Ensign Joseph Coulon de Jumonville and washed his hands in his brains over an insult he had received from the French commander at Fort Duquense.

In Britain, he was reviled as a braggart and cowboy, if we can use the description before it was coined. His letter to his younger brother describing the action was published and include the memorable quote:

“I have heard the bullets whistle; and believe me, there is something charming in the sound.”

Allegedly King George II remarked, “He would not say so if he had been used to hear many.”

Horace Walpole, that trenchant and amusing observer of Georgian England, wrote

“The volley fired by a young Virginian in the backwoods of America set the world on fire.”

In truth, other that Gavrilo Princip, George Washington may very well have the distinction of being the only non-head-of-state to ever singlehandedly set off a world war.

Doubts about Washington were removed forever by the Braddock expedition. On that fateful July day Washington had two horses shot from beneath him and four bullets passed through his coat. His courage and devotion to his commander were noted by all. His reputation for physical courage was bolstered by his accounts reflecting back on Virginia’s elite the views they already held. This powerful combination instantly provided Washington with an entree into the upper reaches of Virginia’s political elite. Because of this he was selected, though still relatively young, to be a delegate to the first Continental Congress. His military reputation made his selection as commander in chief of the infant American army outside Boston a foregone conclusion.