Sun Princess (1980–2001), was an Irish-bred British-trained Thoroughbred racehorse and Broodmare. In a career which lasted from September 1982 until October 1984, she ran ten times and won three races. She recorded all her successes at Group One level when a three-year-old in 1983 winning the Classic Epsom Oaks by a record margin of twelve lengths and the Yorkshire Oaks against other females before defeating colts in the St. Leger Stakes. In the same season she was placed in Europe's two most prestigious all-aged races, finishing third in the King George VI and Queen Elizabeth Stakes and second in the Prix de l'Arc de Triomphe. She raced without winning in 1984 before she was retired to stud, where she became the dam of several winners including the Dewhurst Stakes winner Prince of Dance. Background Sun Princess, a bay filly with a white blaze, was bred by the Ballymacoll Stud in County Meath, Ireland, and raced in the colours of the stud's part-owner Sir Michael Sobell. Sun Princess's sire, English Prince, won the Irish Derby, but was not a great success as a stallion in Europe and was exported to Japan in 1980. Her dam, Sunny Valley, also bred at Ballymacoll, went on to produce the Coronation Cup winner Saddlers' Hall and was the direct female ancestor of the St Leger winner Millenary and the double Breeders' Cup Turf winner Conduit. Like many of the stud's horses, Sun Princess was sent into training with Major Dick Hern at West Ilsley in Berkshire. She was ridden in most of her races by Hern's stable jockey Willie Carson. Racing career 1982: two-year-old season As a young horse, Sun Princess was a challenging horse to train as her temperament made her difficult to settle and she had a tendency to bolt during exercise. Like many of Dick Hern's best horses, she was lightly-campaigned as a two-year-old. She ran once, finishing second in the Blue Seal Stakes at Ascot in September. 1983: three-year-old season Sun Princess made her first appearance as a three-year-old in the Sir Charles Clore Memorial Stakes, at Newbury in May, a trial race for the Epsom Oaks. She ran second to Ski Sailing, finishing twenty-five lengths clear of the third horse. After the race, Carson had a private wager with Ski Sailing's jockey, Steve Cauthen, that he would reverse the placings in the Oaks. At Epsom on 4 June, Sun Princess