Stanhope was introduced into the secretary of state’s office by Lord Chesterfield, was private secretary to Bedford as secretary of state (1748-51), and in 1755 tried to get Bedford to recommend him to Henry Fox as under-secretary.1Bedford to Stanhope, 17 Oct. 1755, Bedford mss. In March 1761 Lord Carnarvon applied to Bute on his behalf. He was appointed under-secretary in 1764 by Lord Halifax, and re-appointed in July 1765 by Grafton; after a few days he resigned on learning that while Grafton wished him ‘to give his whole attendance to the office’, Stonehewer, Grafton’s private secretary ‘only should attend his person and receive his commands’.2HMC 10th Rep. I, 393. In January 1771 he returned to office with Halifax, but in March retired with a pension for life of £564 per annum.
In 1774 Stanhope resigned his law clerkship to stand for Winchester on the interest of the Duke of Chandos (formerly Carnarvon), and was given a secret service pension of £100 (held in trust for him by W. Cory). He was returned unopposed, supported North’s Administration till the end, and voted against Shelburne’s peace preliminaries, 18 Feb. 1783. There is no record of his having spoken in the House. He died 19 Sept. 1783.