The story that Mi tells to Donald about a shipwrecked horse is based on a true story about a New Zealand-bred thoroughbred named "Moiffa" who did in fact survive his ordeal and went on to win the Grand National the following year. In 1979 Mickey Rooney starred in The Black Stallion (1979), which is about a shipwrecked horse that goes on to win a major race.
The race-course map which Mi shows Velvet is an accurate portrayal of the real-life Grand National course at Aintree, near Liverpool. What's more, like the movie, the course actually has a Becher's Brook jump and a Canal Turn jump with its sharp left turn.
Carl and Eleanor Goldbogen appear as extras in the crowd scenes. Carl's brother was Avrom Goldbogen, professionally known as producer Michael Todd, who would become Elizabeth Taylor's third husband in 1957.