Founded in 1728 by the same act of the Virginia Assembly that established neighboring Fredericksburg, Falmouth was created as a port town on the Rappahannock. It served the inhabitants living north of the river within the vast Northern Neck holdings of Lord Fairfax. His agent, Robert "King" Carter, promoted the establishment of the town. The Carter family played a dominant role in the town's growth throughout much of the colonial period. Originally located within King George County, Falmouth became part of Stafford County when county lines were redrawn in 1776.