| Constituency | Dates |
|---|---|
| Old Sarum | 5 Jan. 1742 – May 174726 Feb. 1746 – May 1747 |
| Bridport | 25 May 1747 – 1754 |
| Buckingham | 1754 – 1761, , 1757 – 17681766 – 1768 |
| Horsham | 1768 – Mar. 1770 |
Ld. of Trade 1746 – Dec. 1755; dep. paymaster to forces 1746 – 55; ld. of Treasury Nov. 1756 – Apr. 1757, July 1757 – Mar. 1761; cofferer of the Household Mar. – Oct. 1761; P.C. 3 Apr. 1761; jt. vice-treasurer [I] Aug. 1766-Jan. 1770.
James Grenville was originally brought into Parliament by Thomas Pitt, subsequently resigning his seat to succeed his brother Thomas at Bridport. Like his elder brothers, a member of the political group led by his uncle, Lord Cobham, he at first acted with the Opposition, voting against the Hanoverians in 1742 and 1746, and signing the opposition whip of 10 Nov. 1743. When Cobham opened negotiations with the Pelhams in January 1746, one of his stipulations was that James should be provided with an employment of £1,000 a year, which was provided in the form of a seat on the board of Trade a month later.1Chesterfield to Newcastle, 27 Feb. 1746, Add. 32706, f. 24. In the following April he voted with the Government for the Hanoverians, classed as New Ally. Soon afterwards, according to his brother George, Pitt detached him from his uncle by appointing him deputy paymaster general, which so ‘greatly irritated Lord Cobham’ that he cut James out of his will.2Grenville Pprs. i. 424-5. Writing about 1751, Horace Walpole says that James ‘had all the defects of his brothers and had turned them to the best account’.3Mems. Geo. II, i. 136.
He died 14 Sept. 1783.