When in 1765 a seat at Thirsk was vacated by Henry Grenville, James was returned in his place ‘in consequence of a former agreement made with Mr. Frederick Frankland’.
gave his reasons for not going on against America, because the Americans did not mean to render themselves independent of this country, and because he judged it impracticable to reduce them by force. He concluded by showing with much feeling propriety, that he did not mean to throw any reflection upon the conduct of his late relation Mr. George Grenville.
Grenville now voted consistently with Opposition, and criticized the Administration with increasing vehemence. On 12 Dec. 1781 he supported Lowther’s motion to end the war, and quoted Chatham when after Saratoga he called upon Parliament to ‘relinquish this mad war’.
Grenville, who was appointed a lord of the Treasury by Rockingham, retained the post under Shelburne, having ‘declined in the most positive manner’ to become either chancellor of the Exchequer or secretary at war in the new Administration. Shelburne wrote to the King on 9 July that he was ‘obliged ... in a very particular manner to the assistance of Mr. James Grenville’ who had persuaded his cousin Lord Temple to go to Ireland instead of having the secretaryship for home affairs which he had hoped for. The King replied the same day: ‘I am glad Mr. James Grenville has been of use; I hope he will be cultivated. He is certainly a worthy man.’
Horace Walpole described Grenville as ‘an amiable and ingenious man, who had improved parts, and a most pleasing manner’.
