Born on May 23, 1933 from the mare Swing On and sired by Hard Tack, the bay colt grew up on Claiborne Farm in Paris, Kentucky. He was undersized, knobby-kneed, and not much to look at. Training him for racing was almost an afterthought and the horse was sometimes the butt of people's jokes. In his first 10 races he failed to win and most times finished well back of the field. Then, as a juvenile, Seabiscuit raced thirty five times, winning five times, running second seven times. Still, at the end of the racing season, he was used as a work horse. The next racing season, the colt was again less than spectacular and his owners "unloaded" the horse for $7,500.
His new trainer, Tom Smith, understood the horse and as a four year old, Seabisuit won eleven of his fifteen races and was the leading money winner in the United States that year. However, the great three year old, War Admiral, had won the United States Triple Crown of Thoroughbred Racing that season and was voted "Horse of the Year."
As a five year old, Seabiscuit's success continued and there was much speculation in the media that there would be a match race between him and the seemingly invincible War Admiral. A match race was held but it would not be against War Admiral but instead against a highly regarded horse owned by the Hollywood entertainer Bing Crosby. Seabiscuit won that race and after a few more outings he would finally go head to head with War Admiral in the Pimlico Special in Baltimore, Maryland. In what was dubbed as the "Match of the Century", Seabiscuit ran away from the Triple Crown Champion. As a result of his races that year and the victory over War Admiral, Seabiscuit was named "Horse of the Year" for 1938. When he was retired to the Ridgewood Ranch in California, Seabiscuit, the horse nobody wanted, was the horse racing's all-time leading money winner.
In 1949, a fictionalized story of Seabiscuit was made into a motion picture starring Shirley Temple. At Santa Anita, California racetrack a life-sized bronze statue of Seabiscuit is on display. In 1958, he was voted into the Hall of Fame. In 2001 Laura Hillenbrand wrote Seabiscuit: An American Legend (ISBN 0449005615) that became a bestseller and on July 25, 2003, Universal Studios released a new motion picture titled Seabiscuit.