A bay racehorse facing to the right with his head turned slightly towards the spectator, standing in a stable chained by a head collar to a trough, with a horse blanket bearing the Prince of Wales's feathers on the side.

Diamond Jubilee was the full-brother to Persimmon, who had won the Derby Stakes for the Prince of Wales in 1896 (see RCINs 402227, 402433). Foaled at Sandringham in 1897 by St Simon out of Perdita II, he was named in honour of Queen Victoria's Diamond Jubilee year. Described by his trainer Marsh as a 'faultless horse' he was also aggressive and temperamental. The horse, however, trusted Marsh's young jockey Herbert Jones, and with him in the saddle won six races in 1900 including the 2000 Guineas, the Derby and the St Leger. He was retired to stud at Sandringham in 1902 and four years later was sold to an Argentinian breeder.

It was not unusual for Adam to set his horse 'portraits' within a stable. Two other paintings of Diamond Jubilee at Newmarket are in the Royal Collection (RCINs 402226, 402422).