Painted in 1837 for Lord Augustus Fitzclarence, 1st Earl of Munster (1794 – 1842), eldest of the ten children of William IV and the actress Dorothy Jordan, this miniature was subsequently acquired from the artist by Queen Adelaide in 1839. An earlier payment in Queen Adelaide's accounts to: 'Newton, W.J. a Miniature £100.16.' (96 guineas) is too early (1835 – 6) to refer to this miniature. It shows, however, that Queen Adelaide had commissioned a significant work from her Miniature Painter in Ordinary prior to her acquisition of this posthumous memorial portrait of William IV. The King is shown resting his left elbow on a table beside him next to a plan of the Round Tower of Windsor Castle, wearing a blue coat with the ribbon and star of the Order of the Garter and the neck badge of the Order of the Bath; Windsor Castle is seen in the distance on the left.

Trained by his father, the engraver James Newton, and at the Royal Academy Schools, Newton became established as one of the most fashionable portrait miniaturists of his day. He worked from 1815 to 1863 from studios at nos 6 and 33 Argyll Street, London, exhibiting at the RA 1808 – 63. In 1831, he was appointed Miniature Painter in Ordinary to William IV and Queen Adelaide and he is recorded as painting 13 miniatures of William IV. He was acquainted with Queen Victoria, whom, as Princess Victoria, he had painted in miniature 'only the Head – for a Bracelet' (RA PP/VIC/1900/5393) in 1831. On her accession in 1837 his royal appointment was renewed and he was knighted. However, his work may not have pleased the Queen who commissioned nothing further from him, even though he held his title as Miniature Painter in Ordinary until his retirement in 1858.

Signed, dated and inscribed on the reverse in ink: Portrait of his late Majesty / King William the fourth / Sir W m. J. Newton / Pinxit / Miniature Painter in Ordinary / to Queen Victoria & Queen Adelaide / 68 Argyle Street / 1837. NB This picture was painted for Lord Augustus Fitzclarence. / Queen Adelaide had it of me / Novr 26. 1839 […] W.J.N.