LONDON - Despite not having the budget of some of the giants of the sport such as Irish breeding powerhouse Coolmore Stud or the Maktoum family of Dubai, the British monarch celebrated more than 1,800 winners.
In October 2021, she was recognised for her decades-long contribution to the sport by being inducted into the British Champions Series Hall of Fame, the first person to gain membership as a "special contributor".
The queen's first victory on the turf was with Monaveen over jumps at Fontwell Park in 1949 and she was twice champion flat owner, in 1954 and 1957.
She bred and owned the winner of every British Classic apart from the world-renowned Epsom Derby, triumphing in the 1,000 Guineas, 2,000 Guineas, the Oaks and the Saint Leger.
In a 1974 BBC documentary, the queen, who also rode horses for pleasure throughout her life as well as in ceremonial events, summed up her "simple" racing philosophy.
"I enjoy breeding a horse that is faster than other people's," she said.
"To me, that is a gamble from a long way back. I enjoy going racing but I suppose, basically, I love horses, and the thoroughbred epitomises a really good horse to me.”
The late British monarch, whose mother was also an avid racing fan, came close to winning the Derby in 1953, the year of her coronation, when her horse, Aureole, was beaten by Pinza into second place.
The notoriously highly strung Aureole compensated the following year by winning the race named after the queen's parents, the King George VI and Queen Elizabeth Stakes.
True to form, the racehorse sweated up and dumped his jockey on the turf prior to the start but went on to win.
"Tremendously exciting. Wasn't it a wonderful performance?" the queen was overheard saying on leaving the winners' enclosure.
Her unbridled joy was such that she had a crate of champagne sent to the thirsty reporters in the press room.
Another of her horses, Carlton House, was beaten by less than a length into third in the 2011 Derby.
But while victory in the race remained tantalisingly out of reach, she triumphed at the Epsom Oaks -- a race for three-year-old fillies -- in 1957 with Carrozza and again 20 years later with Dunfermline in the year of her Silver Jubilee.
- 'Passion in life' -
Royal Ascot was a staple event in the queen's busy social calendar, though she was unable to attend this year.
Racegoers and TV viewers witnessed her delight at the event in 2013 when her colours -- purple and scarlet jacket with gold braid and a black cap -- were carried to victory by her horse, Estimate, in the Gold Cup.
"It was so lovely -- she said the grandchildren were behind her in the royal box and they were all shouting and screaming and she said, 'I couldn't hear what was happening'," Kerry Jones, assistant to Estimate's trainer Michael Stoute, told the Toronto Sun newspaper.
"That's when we realised how much she's passionate about her own horses," she said. "It was fascinating."
Camilla, the wife of her eldest son, now King Charles, told ITV Racing in June 2021 that the sport was the queen's "passion in life".
"She could tell you every horse she's bred and owned from the very beginning -- she doesn't forget anything. I can hardly remember what I bred a year ago but she's encyclopaedic about her knowledge."
The queen's racing manager, John Warren, said winning trophies was not her main concern.
"She is not in for the thrill of owning or winning," he told the Evening Standard.
"Competitive is a word I just never associate with the queen. She has never said to me, 'I want to win the Derby.'
"Her majesty once told me: 'My gamble is the breeding'."