After Braddock's defeat in 1755 near Fort Duquesne, all British forces who had arrived with Braddock retreated into Pennsylvania. Once again, the Virginia colony had to rely upon its own resources to deal with a Native American war.
The General Assembly in Williamsburg recycled the defensive strategy adopted in 1676 - build a series of forts to protect farms and settlements. That strategy had been an absolute failure, back when the frontier was further east at the boundary of the Piedmont and Coastal Plain. The failure of colonial leadership to protect the colonists led to Bacon's Rebellion, when the colonial capital of Jamestown was burned and Gov. William Berkeley was forced to flee to the Eastern Shore.
Gov. Dinwiddie appointed George Washington as head of the Virginia militia. Washington recognized that forts located 20 miles from each other offered little protection to most settlers, who would be captured/killed before they could flee to safety. A line of widely-scattered forts would not be an effective barrier to Shawnee raids, so Washington wrote Governor Dinwiddie in early 1756:1
George Washington, dressed in his Virginia militia uniform
Source: Library of Congress, George Washington Papers