August 14, 1733
Chopawamsic, Stafford County, Colony of Virginia
|Died||February 26, 1785
Chopawamsic, Stafford County, Virginia
|Residence||Chopawamsic, Stafford County, Virginia
Raspberry Plain, Leesburg, Virginia
|Citizenship||Kingdom of Great Britain
|Alma mater||College of William and Mary|
|Occupation||lawyer, jurist, Chief Justice of the Supreme Court of Virginia, planter|
|Spouse(s)||Mary King Barnes
Elizabeth Westwood Wallace
|Children||Stevens Thomson Mason
Abram Barnes Thomson Mason
John Thomson Mason
Ann Thomson Mason Chichester
Dorothea Anna Thomson Mason Hirst
Westwood Thomson Mason
William Temple Thomson Mason
George Thomson Mason
|Parents||George Mason III
Ann Stevens Thomson
|Relatives||brother of George Mason IV|
Thomson Mason (14 August 1733 – 26 February 1785) was a prominent Virginia lawyer, jurist, and Chief Justice of the Supreme Court of Virginia. Mason was a younger brother of George Mason IV, United States patriot, statesman, and delegate from Virginia to the U.S. Constitutional Convention, father of Stevens Thomson Mason, a Colonel in the Continental Army during the American Revolutionary War, a member of the Virginia state legislature, and a U.S. Senator from Virginia, and great-grandfather of Stevens T. Mason, first Governor of Michigan.
Early life 
Mason was educated at William and Mary College in Williamsburg, Virginia and then studied law at the Middle Temple in London. Afterwards, he returned to Virginia and was a burgess in the House of Burgesses representing Stafford and Loudoun counties from 1766 to 1775. In 1778, Mason was appointed Chief Justice of the Supreme Court of Virginia and served only briefly before serving as one of five judges in the General Court. From 1779 to 1783, Mason was elected a member of the Virginia House of Delegates and served as chairman of the Committee on Courts of Justice.
Raspberry Plain 
In 1760, Mason purchased Raspberry Plain plantation in Loudoun County, Virginia In 1771, Thomson built the mansion at Raspberry Plain. Upon Thomson's death, the Raspberry Plain estate was deeded to his eldest son Stevens Thomson Mason.
Marriages and children 
- Stevens Thomson Mason (29 December 1760–9 May 1803)
- Abram Barnes Thomson Mason (24 August 1763–12 January 1813)
- John Thomson Mason (15 March 1765–10 December 1824)
- Ann Thomson Mason Chichester (26 February 1769–29 August 1817)
Mary died on 21 October 1771 in Prince William County, Virginia and was interred in the Mason family graveyard at Gunston Hall and later moved to Raspberry Plain. Six years later on 23 November 1777, Mason married for a second time to Elizabeth Westwood Wallace. He and Elizabeth had four children:
- Dorothea "Anne" Anna Thomson Mason Hirst (10 April 1778–5 May 1822)
- Westwood Thomson Mason (20 December 1780–1826)
- William Temple Thomson Mason (24 July 1782–1862)
- George Thomson Mason (died 1873)
Later life 
Mason died on 26 February 1785 at Chopawamsic at the age of 51.
- Gunston Hall. "Thomson Mason". Gunston Hall. Archived from the original on 2008-02-11. Retrieved 2008-02-15.
- The Political Graveyard (June 16, 2008). "Mason family of Virginia". The Political Graveyard. Retrieved 2008-02-15.
- The Colonial Dames of America (1910). Ancestral Records and Portraits: A Compilation from the Archives of Chapter I, the Colonial Dames of America. Boston, Massachusetts: Grafton Press. p. 808.
- Evisum Inc. (2000). "George Mason: Statesman". Virtual War Museum. Retrieved 2008-02-15.
- Raspberry Plain. "Raspberry Plain: History". Raspberry Plain. Retrieved 2009-02-15.
- Hunt Country Celebrations (2008). "Hunt Country Celebrations: Reception Sites". Hunt Country Celebrations. Retrieved 2009-02-15.[dead link]