Charles XII was bred by Major Nicholas Yarburgh of Heslington Hall, Yorkshire, last male heir of a family whose motto was appropriately, 'Non est sine pulvere palma'. Charles XII, by Voltaire out of Wagtail, was one of the most successful horses of his era, winning sixteen out of twenty-three starts. In 1839 he won the Liverpool Summer Cup and the Doncaster St Leger in a very exciting race. Charles XII led from the start, until Thomas Thornhill's Euclid, ridden by Patrick Conolly, snatched the lead in the last furlong. Charles XII rallied to achieve a dead heat. In the run off 'another desperate struggle...ensued, but, at the Stand, Charles got the best of it, and just won by a head' (Thomas Henry Taunton, Portraits of Celebrated Racehorses, London, 1888, vol. III, p. 261.) Two days later Charles XII won the Doncaster Cup, beating the famous Bee's wing.
At the end of 1839 Charles XII was sold for 3,000 gns. to Andrew Johnstone of Helleath House, Dumfriesshire, a partner in Jardine, Matheson & Co., whose declared intent was to spend some of his fortune made in India on one of the finest horses money could buy. In 1840 Charles XII ran six times but only won once, the Grosvenor Stakes. He won the Craven Stakes at Newcastle in 1841 and 1843 and the Goodwood Cup in 1841 and 1843. He retired to stud at Willesden in 1844; his best daughter was Olga (foaled 1851).
Herring painted Charles XII several times, including a portrait of the horse in his stable in 1839, part of Herring's series of Doncaster St Leger winners, which was engraved by C Hunt (see Oliver Beckett, JF Herring & Sons, London and New York, 1981, p. 155; another version illus. in colour pl. v, opposite p.32).