Appointed ensign in the Coldstream guards (May, 1778). Lieutenant in the Rutland regiment (1779).
Member of Parliament for Buckinghamshire (1779-84; 1813-18), Aldeburgh (1790-96), and Buckingham (1796-1809).
Accused the North ministry of discriminating against him with regard to military promotions. Resigned from the army (April, 1780).
A warm friend of Charles James Fox, the secretary of state for foreign affairs. Served as Fox’s envoy to Passy to negotiate peace with the Americans (May-July,1782). Following the death of Lord Rockingham, he refused to serve under Lord Shelburne and was recalled.
Served with Lord Spencer as minister extraordinary to Vienna (1793). Appointed chief justice in Eyre south of Trent (1800). President of the Board of Control (July- October, 1806). First lord of Admiralty (1806-07).
An avid book collector, he bequeathed his library to the British Museum, of which he had been a trustee.
Second son of George Grenville. Brother of George and William Wyndham Grenville. Educated at Eaton (1764-71) and Christ Church, Oxford (1771).