Prince Henry Frederick is wearing naval uniform and the ribbon and star of the Order of the Garter. He was the sixth child and fourth son of Frederick Louis, Prince of Wales (1707–51), and his wife, Augusta (1719–72) of Saxe-Gotha. In July 1766, George III appointed Henry Ranger of Windsor Forest and Great Park and two years later he entered the navy as a midshipman. He was promoted to Rear-Admiral in 1769 and Vice-Admiral in 1770. In 1771, his marriage to Anne Horton horrified George III, and he was barred from the King's presence. In 1775, the Duke became patron of a boat club, the Cumberland Fleet, which was the origin of the Royal Thames Yacht Club. The grey-blue modelling of his face in this painting gives it a slightly bruised appearance which is typical of the work of the artist, Richard Crosse (1742-1810).

Crosse was born near Cullompton, Devonshire. He was a deaf mute and took up miniature painting as a hobby, then went to London to study at Shipley's Drawing School. He was appointed Painter in Enamel to George III in 1788. He painted many leading figures of the day and was a prolific worker – in 1777 he produced about 100 miniatures. Crosse also painted a miniature of the Duke's brother, William Henry Duke of Gloucester (RCIN 420120) and exhibited them both at the Royal Academy in 1771.