Born in
Alexandria, Virginia to the former Sarah Fairfax Carlyle (1757-1827) and her merchant husband William Herbert (1743-1818), John was born to the
First Families of Virginia at the start of the American Revolutionary War. Members of his extended family aligned with both sides in that conflict. His father was a member of the Committee of Safety for Fairfax County, Virginia, and sold supplies to General Washington's army. Two of his maternal relatives, the 7th and 8th Lords Fairfax of Cameron had claims to the
Northern Neck Proprietary, and were Loyalists during the war. His younger (but eldest) sister, Margaret Herbert (1785-1858) married her first cousin Thomas Fairfax, one of the sons of his mother's half-brother, Rev. Bryan Fairfax, who was a personal friend of General Washington and was named the 8th Lord Fairfax of Cameron and the first American-born member of the House of Lords, although he spent his final years in Fairfax County near Alexandria, dying at his plantation house, Mount Eagle. Bryan Fairfax and his progeny, however, did not inherit the Northern Neck Proprietary, which his first cousin Robert Fairfax the 7th Lord Fairfax left to his nephew, Rev. Denny Martin (who remained in England and after considerable litigation attempting to enforce his rights to land rents in the wake of escalating Virginia protection of occupants, sold those vast lands to a group formed by Virginia lawyer and future Chief Justice
John Marshall). Another of Rev. Fairfax's sons, Ferdinando Fairfax, sympathized with the American patriots. His maternal grandfather was prominent Scottish-born merchant
John Carlyle. Another sister, Sarah Herbert, married, Rev. Oliver Norris, and remained in Alexandria, Virginia, as did their mother. Other sisters were Anne, Eliza and Lucinda Herbert. His brother, also William Herbert became a merchant and banker and won election as Alexandria's mayor. As customary for his class, Herbert received private instruction locally, then attended
St. John's College in
Annapolis, Maryland in 1794. Returning to Virginia, he studied law. In 1805 he married Mary Snowden, daughter of Maryland planter Thomas Snowden and his wife Ann, and soon moved to
Prince George's County, Maryland where they lived on a plantation called "Walnut Grange" near
Beltsville. They had thirteen children, many of whom died young. Their daughter Mary Virginia Herbert (1816-1857) married Thomas Triplett Hunter and remained in Maryland. Emma Herbert (1818-1874) married Rev. William Bryant (1800-1846) and moved to southwestern Virginia, where they raised children including John Carlyle Herbert Bryant, some of whom moved back to Alexandria. ==Career==