Active in English county politics. After spending his entire patrimony, he decided to immigrate to America, procured letters of recommendation from Jefferson and Washington, and swore an oath of allegiance before Franklin at Passy (April 1781).
Visited America but soon returned to Paris, where he became involved in Revolutionary politics. Best known for testifying against the comtesse du Barry before the Revolutionary Tribunal (1793). Later settled in Alexandria, Virginia. Published the first English translation Chastellux’s Voyages … dans l’Amerique septentrionale … (1796).
Son of Richard and Elizabeth (Davidson) Grieve of Alnwick, Northumberland.