The sitter was the eldest son of Augustus Henry, 3rd Duke of Grafton (1735-1811) and his wife Anne Liddell. His parents were divorced in 1769 after Anne became pregnant by her lover, John FitzPatrick, 2nd Earl of Upper Ossory. Fitzroy attended Harrow School and then Trinity College, Cambridge where he became a close friend of William Pitt the Younger. He later served as MP for Thetford between 1782 and 1784, and was elected MP for Cambridge University, alongside William Pitt the Younger in 1784, a post which he held until 1811. In 1784, he married Lady Charlotte Waldegrave (1761-1808), daughter of James, 2nd Earl Waldegrave and the couple had ten children. The sitter held a number of offices, including Lord-Lieutenant of Suffolk between 1790 and 1844, Receiver-General in the courts of King’s Bench and Common Pleas, and King’s Gamekeeper at Newmarket. From 1784 to 1807 he was ranger of Hyde Park and St James’s Park, as well as already possessing the hereditary role as ranger of Whittlebury Forest. Euston also became a trustee of the Hunterian Museum and the President of the Eclectic Society of London.

This portrait by George Romney was painted over twelve sittings, held between 26 February and 25 June 1794, and resumed from 8 February to 2 June 1795. The sitter was a contemporary of George Romney’s son, John Romney, at Cambridge and an earlier portrait of him painted in the early 1780s seems to have been mainly painted by John. The present likeness was painted for Charles Pratt, 1st Earl Camden and sent to Ireland after its completion. Romney’s fee of 65 guineas was paid on 18 February 1796. Lord Camden wrote to Romney commending the portrait, saying: ‘I think it is as fine a Picture, of as good a subject for one, as I ever saw’ (Kidson, op.cit., p. 204).