The sitter was the only son of Henry Fitzroy, 1st Duke of Grafton, and his wife Lady Isabella Bennet, only daughter and sole heir of Henry, 1st Earl of Arlington. He succeeded his father in 1690. At the coronation of King George I he was Lord High Steward, and he was also one of the Lords Justices during the King's absence in Hanover. He was later successively Lord-Lieutenant of Ireland from 1720 to 1724, and Lord Chamberlain from 1724 to 1757. He married Henrietta, daughter of Charles, Marquess of Worcester, and granddaughter of Henry, Duke of Beaufort, in 1713, and was succeeded by his grandson, Augustus Henry, after his death from a fall when out riding aged seventy.
Grafton sat to many of the leading portrait painters of the day. This portrait relates to the whole-length by the artist at Euston Hall which seems likely to be the picture engraved by Faber, three-quarter-length, in 1748, as painted in 1739 (see J. Kerslake, National Portrait Gallery, Early Georgian Portraits, I, pp. 99-101), and thus one of the first portraits painted after the artist arrived in London in that year.
The Rt. Hon. Edward Algernon Fitzroy was the second son of Charles, 3rd Baron Southampton. Lieutenant-General Charles Fitzroy, 1st Baron Southampton, was the second son of Lord Augustus Fitzroy, the sitter's third son.