Smythe first became interested in
horse racing as a boy, when he would take stories his father wrote at the track to the newspaper office downtown. Smythe started owning horses in the late 1920s, but he rarely had any success. One early purchase turned out to be one of his most famous. When Mrs. L. A. Livingston sold off her stable, he bought
Rare Jewel, a filly, for $250. The filly regularly ran last. The horse was eligible for the
Coronation Futurity Stakes, one of the best two-year-old races. Smythe was full of blind hope, and on the trainer's advice, entered her in the race. The day of the race, both the trainer and his partner gave the horse some brandy, unknown to Smythe, who bet over $100 on
Rare Jewel. She won the race, a 100–1 longshot paying $214.40 on a $2 bet, besting future
Queen's Plate winner
Froth Blower. Between the winnings from his bets and his portion of the winner's purse as horse owner, Smythe won more than $10,000 on that one race. Three weeks later, he put his windfall to work for the Maple Leafs by purchasing star defenceman
King Clancy from the depression-strapped
Ottawa Senators for $35,000. The purchase was only possible because of his gambling winnings, as the other Maple Leafs owners refused to pay the Senators' then-high price, and only agreed when Smythe volunteered to use his own money. Smythe continued to own horses through the 1930s, but he sold them in 1940, when he made plans to fight in the Second World War. He did not re-enter the racing business until 1954. In 1951, Smythe bought land for a farm in
Caledon, Ontario, originally looking for a new location for a gravel pit. At first he kept only cattle, but in 1954 he decided to get back into owning race horses, in partnership with Larkin Maloney, and an area was set aside to keep horses. Smythe learned about the business and went into breeding, buying mares in foal from top thoroughbred lines, and hiring future Hall of Fame trainer
Yonnie Starr. Maloney and Smythe's most famous horse
Wonder Where, also led to the breakup of the partnership.
Wonder Where, named by Maloney, was bred at Frank Selke's farm in Quebec and bought by Maloney and Smythe in 1957. In 1959,
Wonder Where had an outstanding season, including winning the
Canadian Oaks. The horse was voted
Canadian Horse of the Year for the year and later, the
filly was inducted in the
Canadian Horse Racing Hall of Fame. The
Wonder Where Stakes was established in honour of the horse in 1965, becoming one of the
Canadian Triple Tiara races for fillies in Canada in 1995. After the outstanding year in 1959, Maloney wanted to continue racing
Wonder Where and Smythe did not, concerned over some tendon trouble. The horse broke down in a race in
Fort Erie, and the partnership dissolved after that. Smythe's horses won 145 stakes races during his lifetime, a record second only to
E. P. Taylor in Canada. Smythe's stable won the Queen's Plate twice, the first in 1958 with
Caledon Beau and the second in 1967 with
Jammed Lovely. In 1973, Smythe became a founding member of the
Jockey Club of Canada. In 1977, he was inducted in the Canadian Horse Racing Hall of Fame. After his death, the Smythe stable was sold in 1981 to
Gardiner Farms and
Harlequin Ranches, for an estimated $2.5 million. Smythe's will gave the racing stable to the Conn Smythe Foundation, which as a charitable foundation, could not run a business. The new owners leased back the farm and stables. The only horse not in the sale was
Jammed Lucky, Smythe's favourite, which was given to Smythe's grandson Tommy. The horse had run for Smythe in the 1961 Queen's Plate as one of the favourites and broke a bone in his right foot during the race, but finished the race in eighth place. In 1981,
Jammed Lucky was 23 years old and had sired 25 winning foals to that point. ==Second World War and the conscription crisis==