John Mercer, Sr.

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John Mercer, Sr.

Birthdate: (64)
Birthplace: Ireland
Death: October 14, 1768 (64)
Immediate Family:

Husband of Catherine Mercer and Ann Mercer
Father of James Mercer; Sarah Anne Mason Selden (Mercer); Catesby Mason Mercer; Elizabeth Mason Mercer; George Mercer and 6 others

Managed by: Jacomina Pieternella de Regt
Last Updated:

About John Mercer, Sr.

John Mercer (February 6, 1704 – October 14, 1768) was a colonial American lawyer, land speculator, and author.

Born in Dublin, Ireland, he came to Virginia in 1720 where he built the colonial estate Marlborough (also called Marlboro; at Marlborough Point on the Potomac River, in Stafford County). He was a leading Virginia attorney and lawyer to George Washington, as well as a colonial prosecutor for the King's court of Virginia.

He authored "Dinwiddianae" (4 November 1754-3 May 1757; also known as "The Dinwiddianae Poems and Prose"), "Abridgement of the Public Acts" (1737; also "An Exact Abridgment of the Public Acts of the Assembly of Virginia"), "First Code of Virginia Laws" (1759), and "Abridgment of Virginia Laws" (“Mercer's Abridgement of the Laws of Virginia”). Mercer was also a founding member, secretary and general counsel of the Ohio Company of Virginia, a land speculating company that had George Washington as a member. His private library consisted of between 1500 and 1800 volumes. Did legal work for George Washington land deals as a down payment as a partner, died owing Washington the balance of partnership. His heirs deeded 790 acres (just west of the present day intersection of South Four Mile Run Drive and South Walter Reed Drive in Arlington County, Virginia) to Washington in payment.


Married Catherine Mason (June 21, 1707-June 15, 1750) on June 10, 1725. Married again, after the death of his first wife, to Ann Roy (17??-1770), on November 10, 1750.[11] He had several children (at least 11), many of which (5) died during childhood. Three sons lived to become prominent in Eighteenth Century America:

George Mercer (1733-1784), surveyor, military officer, and politician from Virginia.
James Mercer (1736–1793), judge, lawyer, and jurist who served as a delegate for Virginia to the Continental Congress in 1779.
John Francis Mercer (1759–1821), Captain of the 3rd Virginia during the Revolutionary War, Anti-Federalist at the Constitutional Convention, and Governor of Maryland, 1801-03.

Uncle by marriage to George Mason, became Mason's legal guardian, along with Mason's mother. Mason studied in Mercer's private library. The Mercer Library at the Prince William Campus of George Mason University is named in his honor.

Grandfather of General George Mercer Brooke. Also grandfather of Charles Fenton Mercer (1778-1858; son of James).

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John Mercer, Sr.'s Timeline

February 6, 1704
July 2, 1726
Age 22
December 17, 1727
Age 23
New Town Plantation, Stafford Co., VA
February 16, 1730
Age 26
June 23, 1733
Age 29
Stafford County, Virginia
August 31, 1735
Age 31
February 26, 1736
Age 32
June 25, 1738
Age 34
Stafford Court House, Stafford County, Province of Virginia
August 23, 1740
Age 36
April 9, 1742
Age 38