Prime Minister of Great Britain from 1763 to 1765
Source (Wikipedia): George Grenville

George Grenville was a British Whig statesman who served as Prime Minister of Great Britain, during the early reign of the young George III. He served for only two years (1763-1765), and attempted to solve the problem of the massive debt resulting from the Seven Years’ War. He instituted a series of measures to increase revenue to the crown, including new taxes and enforcement of collection, and sought to bring the North American colonies under tighter crown control.