A dark chestnut colt with a star, snip, and white sock on his near (left) hind leg, The Baron won three of his four starts at the Curragh in Ireland as a three-year-old before being shipped to England in 1845 by his breeder, veterinary surgeon George Watts.

He was then sold to John Scott with whom he won the 1¾-mile St. Leger Stakes and the 2¼-mile Cesarewitch Handicap, the latter under 7 st 9 lb (107 pounds or 49 kilograms) for 3,200 guineas.

Clark sold him to John Mytton, a gambler; after he left Scott, The Baron never won another race.

After Theobald's death, The Baron was sold to Perrot de Thaunberg of France's National Stud.

There he sired many Thoroughbreds, including: Rataplan and Stockwell were full brothers out of the same dam, Pocahontas.