Voltaire (1826 – 16 April 1848) was a British Thoroughbred racehorse. He won five of his six races, including the Doncaster Gold Cup in 1828. After retiring from racing he became a successful stallion, siring St. Leger winner Charles the Twelfth and Voltigeur, who won both The Derby and the St. Leger. He was bred and owned by Robert Stephenson, before being sold to William Vane, Marquess of Cleveland, whom he raced for as a three-year-old.