99% of American horses are sired from one of these two horses
https://en.wikipedia.org/wiki/Northern_Dancerhttps://en.wikipedia.org/wiki/Secretariat_(horse)
Northern Dancer
Northern Dancer (May 27, 1961 – November 16, 1990) was a Thoroughbred that, in 1964, became the first Canadian-bred horse to win the Kentucky Derby. After being retired from racing, he became one of the most successful sires of the 20th century. He is considered a Canadian icon and was inducted into the Canadian Sports Hall of Fame in 1965. In...
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Secretariat (horse)
Secretariat (March 30, 1970 – October 4, 1989), also known as Big Red, was a champion American thoroughbred racehorse who was the ninth winner of the American Triple Crown, setting and still holding the fastest time record in all three of its constituent races. He became the first Triple Crown winner in 25 years and his record-breaking victory...
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