William Nassau de Zuylestein, 4th Earl of Rochford
William Henry Nassau de Zuylestein, 4th Earl of Rochford (1717 – 28 September 1781), was a British diplomat and statesman. Having gained experience as envoy at Turin from 1749 to 1753, he was ambassador at Madrid from 1763 to 1766 and at Paris from 1766 to 1768. From 1768 to 1775 he was Secretary of State successively for the Northern and Southern Departments. He died childless and was succeeded in his peerage titles by his nephew, the 5th Earl.William Henry Nassau de Zuylestein has the dubious honor of being the casting vote in the British parliament when the bill to rescind the "obnoxious" American taxes was voted upon. He voted against the motion, setting the stage for the American Revolutionary War.