Pinckney, Thomas (1750–1828)

US diplomat and soldier. He was governor of South Carolina (1787–89) and ambassador to Great Britain (1792–96). He negotiated the San Lorenzo, or Pinckney, Treaty with Spain, which established territorial and traffic rights on the Mississippi River (1795), and served in the House of Representatives (Federalist, South Carolina; 1797–1801).

Pinckney was born in Charleston, South Carolina. He studied law in London but returned to South Carolina and served with distinction in the American Revolution. A scientific planter, he employed agricultural methods that he had observed in Holland. He was a major general in the War of 1812.