[1] Charles the Twelfth was a "very fine and racing-like" dark brown horse standing sixteen hands high[2] bred by Major Nicholas Yarburgh of Heslington Hall in North Yorkshire.

He was assigned a weight of six stones and six pounds in the Liverpool Tradesmen's Cup, an all-aged handicap race over two miles and started at odds of 5/1 in a field of sixteen runners.

Ridden by a lightweight jockey named Francis, Charles the Twelfth disputed the lead with the five-year-old St Bennett before pulling clear in the closing stages to win easily.

[7] On 17 September Charles the Twelfth was one of fourteen runners (from an original entry of 107) to contest the St Leger Stakes: he was ridden by his trainer's brother Bill Scott and was made the 6/4 favourite ahead of the Derby winner Bloomsbury.

[9] Bill Scott attempted to repeat the tactics he had employed on Don John the previous year by taking the lead shortly after the start and setting a very fast pace.

Most of the other horses were well-beaten before the turn into the straight, but as Charles the Twelfth approached the final furlong Euclid, ridden by Patrick Conolly, emerged as a serious challenger.

The early stages deciding heat, for which Euclid started a slight favourite, were run at a very slow pace, as both jockeys attempted to employ waiting tactics.

[11] Two days later Charles the Twelfth was matched against older horses, including the leading stayers Bee's-wing and Lanercost in the Doncaster Cup over two miles five furlongs.

At the Royal Caledonian Hunt meeting at Stirling in October, he won a 50 sovereign race over two miles, and walked over for the Challenge Whip and a Queen's Plate.

[21] Charles the Twelfth began his six-year-old season with another race against Bee's-wing and was beaten four lengths by the mare at weight-for age in the Gold Cup at Newcastle in June.

Ridden by Jem Robinson and carrying top weight of 135 pounds, he won by two lengths from the three-year-old Policy to take the Cup for the second year in succession.

[24] Later that month Charles the Twelfth ran at Kelso where he finished second to Cabrerea in the Roxburgh Gold Cup and was beaten when attempting to concede 40 pounds to the three-year-old Whistle Blinkie in a two and a half-mile handicap.

[25] On 7 October at the Royal Caledonian Hunt meeting at Perth Racecourse Charles the Twelfth retained the Challenge Whip by beating Foxberry over two miles.