Northern Dancer (May 27, 1961 – November 16, 1990) was a Thoroughbred who, in 1964, became the first Canadian-bred horse to win the Kentucky Derby. He then 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. Induction into the Racing Hall of Fame in both Canada and the United States followed in 1976. As a competitor, The Blood-Horse ranked him as one of the top 100 U.S. Thoroughbred racehorses of the 20th century. As a sire of sires, his impact on the breed is still felt worldwide.

At age two, Northern Dancer was named the Canadian Champion Two-Year-Old Colt after winning both the Summer Stakes and Coronation Futurity in Canada, plus the Remsen Stakes in New York. At three, he became a leading contender for the Kentucky Derby with wins in the Flamingo Stakes, Florida Derby, and Blue Grass Stakes. Northern Dancer followed up a record-setting victory in the Kentucky Derby by winning the Preakness Stakes. With a chance at the American Triple Crown, he finished third in the Belmont Stakes. Returning to Canada for a hero's welcome, he then won the Queen's Plate in what proved to be his last race.

Northern Dancer retired to stud in 1965 at Windfields Farm in Oshawa, Ontario, Canada. He was an immediate success when his first crop reached racing age in 1968, and the success of his second crop, led by English Triple Crown winner Nijinsky, brought his name to the international stage. Northern Dancer was relocated to the Maryland branch of Windfields Farm, where he became the most sought sire of his time.