An embassy from King Louis XI of…

Washington had returned to Williamsburg and informed Dinwiddie that the French had refused to leave.

Dinwiddie commissions Washington a lieutenant colonel, and orders him to begin raising a militia regiment to hold the Forks of the Ohio, a site Washington had identified as a fine location for a fortress.

Even before learning of the French refusal to decamp, Dinwiddie had issued a captain's commission to Ohio Company employee William Trent, send a small force of Virginia militia in January 1754 to build a fort at the forks of the Ohio River, where the Allegheny and Monongahela rivers merge to form the Ohio at present-day Pittsburgh.

Dinwiddie had issued these instructions on his own authority, without even asking for funding from the Virginina House of Burgesses until after the fact.

Trent's company had arrived on site on February 1754, and began construction of a storehouse and stockade with the assistance of Tanacharison and the Mingos.

Work began on the fort on February 17, but by April a much larger French force of eight hundred Canadien militia and French troupes de la marine under the command of Claude-Pierre Pécaudy de Contrecœur, who has taken over command from Saint-Pierre.

When Contrecœur learns of Trent's activity, he leads a force of about five hundred men (troupes de la marine, militia, and natives) to drive them off (rumors reaching Trent's men put its size at one thousand).

Contrecœur's force arrives at the forks on April 16; the next day, Trent's force of thirty-six men, led by Ensign Edward Ward in Trent's absence, agree to leave the site.

The French now begin construction of the fort they called Fort Duquesne in honor of the Marquis de Duquesne, the current governor of New France.

The fort is built on the same model as Fort Frontenac on Lake Ontario.

Meanwhile, at Fort Duquesne, the French garrison consists of only about two hundred and fifty regulars and Canadian militia, with about six hundred and forty native allies camped outside the fort.

The natives are from a variety of tribes long associated with the French, including Ottawas, Ojibwas, and Potawatomis.

Claude-Pierre Pécaudy de Contrecœur, the Canadian commander, receives reports from native scouting parties that the British are on their way to besiege the fort.

He realizes he cannot withstand Braddock's cannon, and decides to launch a preemptive strike, an ambush of Braddock's army as he crosses the Monongahela River.

The native allies are initially reluctant to attack such a large British force, but the French field commander Daniel Liénard de Beaujeu, who dresses himself in full war regalia complete with war paint, persuades them to follow his lead.

This collapse of native support makes it impossible for the French to hold Fort Duquesne and the Ohio Valley.

When the expedition nears to within a few miles of Fort Duquesne in mid-November, the French abandon and blow up the fort.

Three units of scouts led by Captain Hugh Waddell enter the smoking remnants of the fort under the orders of Colonel George Washington on November 24.

General Forbes, who is ill with dysentery for much of the expedition, only briefly visits the ruins.

He is returned to Philadelphia in a litter, and dies not long afterward.

The collapse of native support and subsequent withdrawal of the French from the Ohio Country helps contribute to the "year of wonders", the string of British 'miraculous' victories also known by the Latin Annus Mirabilis.