Grenville was the second son of
James Grenville and was the twin brother of
James Grenville, 1st Baron Glastonbury. He attended
Eton College from 1754 to 1758, Grenville obtained the rank of captain in 1760, by raising an independent company, and on 7 May 1761 he was removed to a company in the
24th Regiment of Foot. He served the campaigns of 1761 and 1762 in Germany, as aide-de-camp to
the Marquess of Granby. In 1772 he purchased a company in the
Coldstream Guards, and in 1776 he accompanied the brigade of Guards to America. On 19 February 1779 he received the rank of colonel, on 20 November 1782 that of major-general, on 21 April 1786, the colonelcy for life of the
23rd Regiment of Foot, and on 3 May 1796 the rank of lieutenant-general. In 1798 he was appointed commandant of the garrison at Plymouth in the absence of
the Governor, and on 1 January 1801 he was promoted to general. Grenville was returned as
Member of Parliament for
Buckingham, together with his twin brother James, on the family interest at the
1774 general election. His military activities appear to have prevented him from making much of a contribution in Parliament. Whether by his own choice or at the instigation of Lord Temple, he did not stand in
1780. Grenville was in charge of
Prince Frederick Augustus's establishment in Hanover from about 1781 until 1787, then served as comptroller and master of the Household to him as Duke of York from 1788 until 1823. Grenville died unmarried in 1823. ==References==