The list below shows the leading sire of Thoroughbred racehorses in North America for each year since 1830. This is determined by the amount of prize money won by the sire's progeny during the year. It is restricted to stallions which are based in North America, but currently includes earnings from overseas races in Great Britain, Ireland, France, Italy, Germany and the United Arab Emirates as well as domestic earnings.
Prior to 2015, the Leading Sire Lists published by The Blood-Horse excluded earnings from Hong Kong and Japan due to the disparity in purses. Starting in 2015, earnings from Hong Kong and Japan are included on an adjusted basis. [1]
Nearco was an Italian-bred Thoroughbred racehorse described by Thoroughbred Heritage as "one of the greatest racehorses of the Twentieth Century" and "one of the most important sires of the century." He was unbeaten, winning 14 races at distances from 1000m to 3000m, including the Derby Italiano and Grand Prix de Paris. He was then sold for a record amount to Martin H. Benson and stood stud in England, where he became the patriarch of several of the most dominant sire lines in Thoroughbred history.
The Travers Stakes is an American Grade I Thoroughbred horse race held at Saratoga Race Course in Saratoga Springs, New York. It is nicknamed the "Midsummer Derby" and is the third-ranked race for American three-year-olds according to international classifications, behind only the Kentucky Derby and Belmont Stakes. First held in 1864, it is the oldest stakes race in the United States specifically for 3-year-olds, and was named for William R. Travers, the president of the old Saratoga Racing Association. His horse, Kentucky, won the first running of the Travers. The race was not run in 1896, 1898, 1899, 1900, 1911, and 1912.
Bold Ruler was an American Thoroughbred Hall of Fame racehorse who was the 1957 Horse of the Year. This following a three-year-old campaign that included wins in the Preakness Stakes and Trenton Handicap, in which he defeated fellow Hall of Fame inductees Round Table and Gallant Man. Bold Ruler was named American Champion Sprinter at age four, and upon retirement became the leading sire in North America eight times between 1963 and 1973, the most of any sire in the twentieth century.
Glencoe (1831–1857) was a British bred Thoroughbred racehorse, who won the 2,000 Guineas Stakes and the Ascot Gold Cup. He was one of the earliest Thoroughbred stallions imported into the United States and was a top broodmare sire there. Several outstanding sons of Lexington were out of Glencoe mares, including Asteroid, Kentucky and Norfolk.
Reel was a thoroughbred race horse, and one of the greatest American Thoroughbred broodmares in history.
Claiborne Farm is a thoroughbred horse breeding operation near Paris, Kentucky. It was established in 1910 by Arthur B. Hancock, owner of Ellerslie Stud in Albemarle County, Virginia, and has been operated by members of his family ever since.
Lexington was a United States Thoroughbred race horse who won six of his seven race starts. Perhaps his greatest fame, however, came as the most successful sire of the second half of the nineteenth century; he was the leading sire in North America 16 times, and broodmare sire of many notable racehorses.
La Troienne (1926–1954) was one of the most famous and influential Thoroughbred broodmares in twentieth century America. She produced 10 winners including two Hall of Fame inductees while at stud, while her daughters in turn produced many notable offspring. In 2000, pedigree expert Janeen Oliver designated her as the taproot of family 1-x, a designation that was implemented by the Pedigree Online Thoroughbred Database in 2003. Recent matrilineal descendants include 2003 Horse of the Year Mineshaft, Japanese Triple Crown winner Contrail (2020), Kentucky Derby winners Smarty Jones (2004) and Super Saver (2010), Belmont Stakes winner Essential Quality (2021), and Sussex Stakes winner Alcohol Free (2021).
The list below shows the leading Thoroughbred sire of broodmares in North America for each year since 1924. This is determined by the amount of prize money won during the year by racehorses which were foaled by a daughter of the sire. The most frequent sires on the list are Sir Gallahad III (12), Mr. Prospector (9), Princequillo (8), and Star Shoot (5).
Teddy (1913–1936) was a French racehorse and an influential sire, especially for lines in Italy, France, and the United States. He is considered one of the most influential sires in the 20th century.
Bull Lea was an American Thoroughbred racehorse who is best known as the foundation sire responsible for making Calumet Farm one of the most successful racing stables in American history. In their article on Calumet Farm, the International Museum of the Horse in Lexington, Kentucky wrote that Bull Lea was "one of the greatest sires in Thoroughbred breeding history."
Pulpit was an American Thoroughbred racehorse who won the Fountain of Youth Stakes and Blue Grass Stakes and came fourth in the 1997 Kentucky Derby. Injured after that race, he retired to stud at Claiborne Farm near Paris, Kentucky where he became a successful sire. His descendants include leading sire in North America Tapit and multiple American Classic winners such as Tonalist and California Chrome.
Bull Dog (1927–1954) was a French Thoroughbred racehorse who became a North American Champion sire and Champion broodmare sire.
Tapit is an American Thoroughbred racehorse who won three of his six races, including the Wood Memorial Stakes, then a Grade I event. He was an immediate success after retiring to stud, becoming the leading freshman sire in North America of 2008 with Breeders' Cup winner Stardom Bound becoming his first Grade I winner. He was the leading sire in North America in 2014, setting an earnings record that he broke in 2015 and again in 2016. For the 2015 season, his stud fee was raised to $300,000, the highest in North America. In 2021, Essential Quality became his fourth Belmont Stakes winner, tying him for the all-time record of winners sired in this race with the great Lexington.
Gen. Duke (1954–1958) was an American Thoroughbred racehorse who won the 1957 Florida Derby.
The Kentucky Broodmare of the Year is selected each year by the Kentucky Thoroughbred Owners and Breeders Association. The title is considered the highest honor an American thoroughbred broodmare can receive, as the majority of American breeding stock resides in Kentucky. It is a subjective vote, as opposed to the title for leading sire in North America that looks strictly at the earnings of the stallion's progeny in the given year.
Arthur B. "Bull" Hancock Jr. was a breeder and owner of thoroughbred racehorses at Claiborne Farm in Paris, Kentucky, United States. He acquired European horses to breed in the United States, in particular Nasrullah and Princequillo, and gained great standing in the racing world as a result.
Average earnings index (AEI) is a popular statistic used in North American Thoroughbred horse breeding. It is used to put the earnings of a breeding animal's progeny into proper perspective.
Into Mischief is a retired American Thoroughbred racehorse and active sire. During his racing career, he won three of six starts including the CashCall Futurity. Since his retirement, he has developed into an outstanding sire, leading the North American sire list in 2019, 2020, 2021, 2022, and 2023. His offspring include Authentic, Mandaloun, Life Is Good and Covfefe.
Miss Disco (1944–1974) was an American Thoroughbred racemare that won important sprint events against colts during her racing career but who secured her place in history when, as a broodmare at Claiborne Farm, she was bred to Nasrullah and produced the very influential National Champion and Hall of Fame sire Bold Ruler.