 He was a justice of the peace and a captain of horse in 1680.He was a member of the Virginia House of Burgesses in 1693, 1696, 1699, and one of the committee in 1700 reporting a revision of the laws which were approved by the General Assembly in 1705.Captain Armistead married Hannah Ellyson, daughter of Dr. Robert Ellyson, of James City County, Virginia.