Glad Rags is a Thoroughbred

Thoroughbred

The Thoroughbred is a horse breed best known for its use in horse racing. Although the word thoroughbred is sometimes used to refer to any breed of purebred horse, it technically refers only to the Thoroughbred breed...

 racehorse

Horse racing

Horse racing is an equestrian sport that has a long history. Archaeological records indicate that horse racing occurred in ancient Babylon, Syria, and Egypt. Both chariot and mounted horse racing were events in the ancient Greek Olympics by 648 BC...

 best known for giving renowned trainer

Horse trainer

In horse racing, a trainer prepares a horse for races, with responsibility for exercising it, getting it race-ready and determining which races it should enter...

 Vincent O'Brien

Vincent O'Brien

Dr. Michael Vincent O'Brien was an Irish race horse trainer from Churchtown, County Cork, Ireland. In 2003 he was voted the greatest influence in horse racing history, according to a worldwide vote hosted by the Racing Post newspaper...

 his only win in the British Classic 1,000 Guineas Stakes.

Glad Rags was owned by American Alice du Pont Mills

Alice du Pont Mills

Alice Francis du Pont Mills was an American aviatrix, thoroughbred race horse breeder and owner, environmentalist, philanthropist and a member of the prominent du Pont family....

, a member of the prominent Du Pont family

Du Pont family

The Du Pont family is an American family descended from Pierre Samuel du Pont de Nemours . The son of a Paris watchmaker and a member of a Burgundian noble family, he and his sons, Victor Marie du Pont and Eleuthère Irénée du Pont, emigrated to the United States in 1800 and used the resources of...

 who was an advisory trustee to the National Museum of Racing and Hall of Fame

National Museum of Racing and Hall of Fame

The National Museum of Racing and Hall of Fame was founded in 1950 in Saratoga Springs, New York, to honor the achievements of American thoroughbred race horses, jockeys, and trainers...

 at Saratoga Springs, New York

Saratoga Springs, New York

Saratoga Springs, also known as simply Saratoga, is a city in Saratoga County, New York, United States. The population was 26,586 at the 2010 census. The name reflects the presence of mineral springs in the area. While the word "Saratoga" is known to be a corruption of a Native American name, ...

, and a director of the American Grayson-Jockey Club Research Foundation.

Following her retirement from racing, Glad Rags was sent to the United States to serve as a broodmare. She produced eleven foals by preeminent stallions

Stallion (horse)

A stallion is a male horse that has not been gelded .Stallions will follow the conformation and phenotype of their breed, but within that standard, the presence of hormones such as testosterone may give stallions a thicker, "cresty" neck, as well as a somewhat more muscular physique as compared to...

  Alydar

Alydar

Alydar was a chestnut colt and an American thoroughbred race horse who was most famous for finishing a close second to Affirmed in all three races of the Triple Crown of Thoroughbred Racing, a feat not achieved before or repeated since.-Racing career:Trained by John M...

, Buckpasser

Buckpasser

Buckpasser was an American-bred Thoroughbred racehorse who won he won nine of his eleven race starts for international record winnings for a two-year-old of $586,090. Buckpasser was leading broodmare sire in 1983, 1984 and 1989....

, Hoist The Flag

Hoist The Flag

Hoist The Flag was an American Champion Thoroughbred racehorse. Bred by New York City Investment banker, John Schiff, he was out of the mare Wavy Navy, a daughter of the 1937 U.S. Triple Crown champion, War Admiral...

, Native Dancer

Native Dancer

Native Dancer , nicknamed the Grey Ghost, was one of the most celebrated and accomplished Thoroughbred racehorses in history, the first horse made famous through the medium of television. He was one of the best horses produced in USA after the war...

, Nijinsky

Nijinsky II

The racehorse Nijinsky was one of the greatest horses in Thoroughbred horse-racing history. He won the U.K. Triple Crown of racing. Retired to stud he became the Leading sire in Great Britain & Ireland and the Leading broodmare sire in North America.He was bred at E. P...

, Raise a Native

Raise a Native

Raise a Native was an undefeated Thoroughbred racehorse that was named 1963 champion two-year-old colt in the Turf and Sport Digest poll. He sired 74 stakes winners, including Majestic Prince and Alydar...

, Sir Ivor

Sir Ivor

Sir Ivor was an American-bred Thoroughbred racehorse who competed from a base in Ireland. Owned by American businessman and U.S. Ambassador to Ireland, Raymond R...

.