Revolutionary War Continental Army Officer, US Congressman, South Carolina Governor, US Diplomat. Born in Charleston, South Carolina, at the age of three, his family traveled to Britain where his father served as a colonial agent to the Board of Trade. He attended Westminster School, Oxford, England, and was graduated from Oxford University, England. He attended the French Military College, Caen, France, for one year; and studied law at the Inner Temple, London. He was admitted to the bar in 1774. He returned to South Carolina that same year. In 1775, he was commissioned a captain of Engineers, First South Carolina Regiment, Continental Army. He was promoted to major in the Florida campaign of 1778; he served under General Benjamin Lincoln in 1778 and 1779; and with Count d’Estaing in 1779. During the Battle of Camden in 1780, he was wounded and taken prisoner. He remained a prisoner of war for more than a year before he was released in a prisoner exchange and was active in the defense of Charleston. After the war, he served as Governor of South Carolina from 1787 to 1789, and presided over the state convention which ratified the US Constitution. He was then elected to the House of Representatives in 1791. The following year, President Washington appointed him ambassador to Great Britain. He also served as Envoy Extraordinary to Spain and negotiated the Treaty of San Lorenzo, better known as Pickney's Treaty, in 1795, by which the boundary between the United States and Spanish holdings were was settled and Spain relinquished all claims east of the Mississippi above Florida, while the United States secured the freedom of navigation of the Mississippi. This success placed him in good standing with political movers, and the Federalists ran him as their presidential candidate in 1796. He took a seat in the House of Representatives to fill the vacancy caused by a resignation, and he served from November 1797 to March 1801. After his tenure, he resumed his law practice and ran his plantation; he was a frequent contributor 'Southern Agriculturist.' He was appointed major general during the War of 1812 and served throughout, before again retiring to his estates. From 1825, he served as president general of the Society of the Cincinnati until his death.