The Merry Monarch was a bay horse bred by his owner, William Gratwicke of Ham Manor, near Angmering in Sussex.

[6] Ridden by the little-known Foster Bell, The Merry Monarch started at odds of 15/1 in a record field of thirty one runners.

The Merry Monarch was among the leading group from the start, and was in fourth place at the turn into the straight, where one horse fell and several others were badly hampered.

[9] Approaching the final furlong, Bell sent The Merry Monarch to the front and he established a clear lead before staying on well to win "in clever style" by a length from Annandale, with Old England a neck away in third.

[10] The result was a major surprise to most observers, including, it was reported, the winner's own connections,[11] who had believed that their other runner, Doleful, had the better chance of winning.

The Merry Monarch's prize of £3,975 for the Derby was enough to make him the third highest money winner of the British season behind Refraction and Sweetmeat.

[14] On his only race as a four-year-old, The Merry Monarch returned to Epsom for the Grand Stand Plate, a mile and a quarter handicap on the day after the Derby.

[16] The Sportsman magazine described The Merry Monarch as "a very bad horse" and his Derby win as the biggest "fluke" in the history of the race.