His father gave this man 300 acres of land on March 16, 1752, likely on the occasion either of his 21st birthday (hence reaching legal age) or as a wedding gift, since he married Mary Eppes that year. Mason bought a 1400-acre tract on the north side of Three Creeks from William and Sarah Avent. The area was also known as Joseph or Otterdam Swamp, and the house Mason constructed and called "Shell Bank" survived in considerable disrepair until razed in the mid-1940s. Mason, presumably like his father and in-laws, was a planter and used enslaved labor to operate his plantations. In 1776, he followed his father's example and gave 746 acres on the north side of the Three Creeks to his son Thomas Mason, who married the following year, although after the conflict Thomas Mason lived on the north side of Poplar Swamp in the Henry Crossroads area and in 1812 may have moved his family to
Southampton County, although the 1820 census shows him as owning 21 slaves in Sussex County. In the 1787 Virginia tax census, his eldest son Littleberry Mason owned 12 Blacks more than 16 years old, 20 younger slaves, as well as eight horses, 35 cattle and a 2-wheeled carriage. As explained below, if John Mason and/or Peyton Mason were also sons rather than nephews, they also owned slaves in Sussex County in 1787. Also to the extent they were this man's sons, Nathaniel Mason owned 8 adult slaves and 11 enslaved children in
Brunswick County, and William Mason owned nine adult and seven enslaved children in
Greensville County. In 1756 Mason became one of the early justices of the peace for Sussex County (established from Surry County in 1754, with his elder brother having been one of the initial justices and remaining in office). David Mason remained such for 17 years, as well as served as the county treasurer. Before the
American Revolutionary War, Mason represented Sussex County for nearly two decades in the House of Burgesses, beginning in 1758 alongside veteran politician John Edmunds for over a decade until Edmunds' death in 1770, then in the next two sessions alongside first James Bell, then Richard Blum (who also died), and finally alongside Michael Blow from 1774 until
Governor Dunmore dissolved that legislative body. As the schism with Britain widened, Mason served in all five Virginia Revolutionary Conventions, including on a drafting committees with non-relative
George Mason. David Mason represented Sussex County alongside Michael Blow in the first Virginia Revolutionary Convention, then he and Henry Gee represented Sussex County for the next four revolutionary conventions, before creation of the
Virginia House of Delegates and
Senate of Virginia. Mason and Gee had both held local offices as well as served on the Albemarle Parish vestry and in 1775 on the county's 28-member
Committee of Safety. Mason served as colonel of the
15th Virginia Regiment beginning in 1777, with his eldest son Littleberry Mason (1753-1807) as the regimental paymaster. Col. Mason later commanded a regiment. While this man as Colonel was responsible for equipping and inoculating the local militia, and gave his bond on June 8, 1776, his nephew Captain James Mason was responsible for organizing the local militia in the conflict. Complicating matters, other men named David Mason, served as enlisted man with the 5th and as lieutenant then captain in the 11th Virginia Regiment. Perhaps because this Col. Mason took an unauthorized trip back to visit his wife during the conflict, he was not named the County Lieutenant (head of the county militia) in 1785 by Gov.
Patrick Henry, and soon may have left the county, as his legislative service detailed below also ended. In 1776 Mason was elected to the Virginia Senate for the district consisting of
Dinwiddie,
Southampton and Sussex Counties, but
Edwin Gray succeeded him the following year. Mason was again elected to the Virginia Senate in 1779, as Gray and perhaps longtime county clerk Augustine Claiborne (who had won prior elections for the seat) were disqualified. Mason then ended his overt political career by serving in the
Virginia House of Delegates during the 1782 session. ==Personal life==