Bloomsbury had been bred by Robert Ridsdale who, upon entering financial dificulties, was forced to sell his stables. Bloomsbury was left unbid and passed to William Ridsdale, his brother, the trainer to Lord Chesterfield. Bloomsbury was subsequently bought by Harry Hill, the bookmaker, who took over all the Ridsdale's remaining debts and entered the horse into the 1839 Derby with John Day as jockey. Against all expectations Bloomsbury won the race which took place in a blizzard.