The term "Test of the Champion" dates from the late 1940s. In the 2000s, the Belmont Stakes also began to be called the "Run for the Carnations."
Wikipedia: Belmont Stakes
The Belmont Stakes is an American Grade I stakes race held every June at Belmont Park in Elmont, New York. The race is the third and final leg of the Triple Crown, following five weeks after the Kentucky Derby, and three weeks after the Preakness Stakes. It is a 1.5-mile (2.4 km) thoroughbred horse race for three-year-old colts and geldings carrying a weight of 126 pounds (57 kg) and for fillies with a weight of 121 pounds (55 kg). The attendance at the Belmont Stakes ranks fourth in North America and usually surpasses the attendance of all other stakes races including the the Breeders' Cup. The attendance of the Belmont Stakes typically only trails the Kentucky Derby, the Preakness Stakes and the Kentucky Oaks, for more information see American Thoroughbred Racing top Attended Events.
The Belmont Stakes is called the "Run for the Carnations" because of the blanket of white carnations that is draped over the winner's neck. Through 1996, the post parade song was "Sidewalks of New York." Beginning in 1997, the audience was invited to sing the Theme from New York, New York following the call to the post. This tradition mirrors the singing of two other songs at the post parades of the first two Triple Crown races, My Old Kentucky Home at the Kentucky Derby and Maryland, My Maryland at the Preakness Stakes.
The first Belmont Stakes was held at Jerome Park Racetrack in The Bronx, built in 1866 by stock market speculator Leonard Jerome (1817–1891) and financed by August Belmont, Sr. (1816–1890) for whom the race was named. The race continued to be held at Jerome Park until 1890 when it was moved to the nearby facility, Morris Park Racecourse. The race remained there until the May 1905 opening of the new Belmont Park, 430 acre (1.7 km²) racetrack in Elmont, New York.
Anti-betting legislation was passed in New York State, closing Belmont and canceling the race for two years between 1911 and 1912.
The first post parade in the United States was at the 14th Belmont, in 1880. Before 1921, the race was run in the clockwise tradition of English racing. Since then, the race has been run in the American or counter-clockwise direction. The winner of the Belmont Stakes is presented the August Belmont Trophy one of the most prestigious trophies in the country.
Because of its length (one lap around the enormous Belmont main track), and because it is the final race of the Triple Crown, it is called the "Test of the Champion". Most three-year-olds are unaccustomed to the distance, and lack the experience, if not the stamina, to maintain a winning speed for so long. In a long race such as the Belmont, positioning of the horse and the timing of the move to chase for the lead can be critical.
22 May 1943. New York (NY) Times, p. 17:
Count Fleet and five others have been named for the historic WIthers Stakes, $15,000 added feature at Belmont Park today, that will serve as a test of the champion's ability to come down to a mile from the longer routes he has been running.
11 June 1949. New York (NY) Times, p. 14:
At that time, if the starting fee of $750 is paid for each, eight colts of that age will go into the starting gate at Belmont Park for the eighty-first running of the Belmont Stakes, "test of the champion" in the division.
Daily Racing Form Online
11 May 1951, Daily Racing Form, "Judge's Stand" by Charles Hatton, pg. 44:
For example, the first three in the Kentucky Derby are ineligible for the Preakness, so perhaps the Belmont Stakes on June 16 will actually be "The Test of the Champion," as it has been billed.
Daily Racing Form Online
13 June 1953, Daily Racing Form, pg. 6:
Widener Wholeheartedly Agrees That
Belmont Stakes Is "Test of Champion"
By BOB HORWOOD
BELMONT PARK, Elmont, L. I., N. Y., June 12. -- The Belmont Stakes, which will have its 85th running tomorros, is advertised as "the test of the champion," and George D. Widener, in his dual role as chairman of The Jockey Club and president of the Westchester Racing Association makes it clear that he feels this is an accurate appraisal of the classic mile and one-half so far as the conditions of the race are concerned.
5 June 1970. New York (NY) Times, p. 45:
Although it does not compare to last year's running, when previously undefeated Majestic Prince and Arts and Letters held the public interest, this year's Belmont Stakes is attracting more than mild attention. The main reason is the presence in the field of Mrs. Ethel D. Jacob's Personality and High Echelon.
The Jacobs entry continued to be rated the favorite for tomorrow's mile-and-a-half "test of the champion."
5 June 1976. New York (NY) Times, p. 41:
At a mile and one-half, the Belmont Stakes is known as the Test of a Champion.
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