Clinton served in Canada during the war of the Austrian succession and in Germany during the seven years’ war. He was a cousin of Henry, 2nd Duke of Newcastle, and was returned on the Newcastle interest at Boroughbridge and Newark. In the House of Commons he was a regular Government supporter. From 1775 to 1782 he was in America, holding military posts of crucial importance. He seems to have been unequal to his responsibilities. ‘Though I believe him ... a brave and honest man’, wrote G. B. Rodney to Germain, 22 Dec. 1780,1HMC Stopford-Sackville, ii. 192. ‘I am convinced nature has not given him an enterprizing and active spirit, capable of pushing the advantages he may have gained in battle.’ Differences, first with Howe and then with Cornwallis, made his task no easier; and in April 1782, after repeated requests to resign his command, he was allowed to return to England.
Clinton voted against Shelburne’s peace preliminaries, 18 Feb. 1783, and supported the Coalition. In July 1783 North applied to the King for an Irish viscountcy for Clinton, but could only obtain his agreement to a barony. Whereupon, William Windham reported to Lord Northington, the lord lieutenant, 17 July, Clinton ‘was understood to have refused his peerage, not being able to succeed as to being a viscount’.2Add. 33100, ff. 189, 190, 205. On 25 and 27 June 1783 he spoke for a motion to grant half pay to American Loyalist officers—his only recorded interventions in debate. He voted for Fox’s East India bill, 27 Nov. 1783; was classed by Robinson in January 1784 as ‘hopeful’ and in Stockdale’s list of 19 Mar. as ‘absent’. Newcastle did not return him at the general election of 1784.
After his return to England Clinton pressed for an inquiry into his conduct as commander-in-chief in America; on this being refused him, he published a pamphlet for his own justification, and wrote but never published a more elaborate apologia.3‘An Historical Detail of Seven years Campaigns in North America’, ed. 1954 by W. B. Willcox as The American Rebellion.
Clinton died 23 Dec. 1795.