William Byrd III (1728–1777) was appointed, in the mid-1750s, a member of the Virginia Council. He lived at his family’s James River plantation called Westover, located in Charles City County, Virginia. He also held extensive lands in many other counties, including Lunenburg, which he represented in the House of Burgesses from 1752 to 1754. In 1758, Byrd became colonel of the 2d Virginia Regiment, and he later succeeded GW as colonel of the 1st Virginia Regiment.
In the 1760s, Byrd rented a house and lots in Williamsburg, Va., which were part of the Custis estate.