1945: two-year-old season Souverain ran only once as a two-year-old, winning a race over 1800
metres (nine
furlongs).
1946: three-year-old season Souverain recorded his first important success when he won the three-year-old version of the Prix Jean Prat over 2000 metres at
Longchamp Racecourse in April. A month later he finished third to Adrar in the 2400 metre
Prix Hocquart. The colt returned to Longchamp in July for the 3000 metre Grand Prix de Paris for which he started a 53.5/1 outsider. Ridden by Marcel Lollierou he won by a short head from the
Prix du Jockey Club winner
Prince Chevalier. then a relatively new technology which was not introduced to Britain until 1947. In October, Souverain recorded another important success when he defeated Prince Chevalier in "storming fashion" Ridden as usual by Lollierou, Souverain "shot clear" of the field in the straight and won easily by five lengths from Bright News, with Airborne, the favourite, in third. The success of Souverain reportedly "shattered" the belief of British breeders in the superiority of their staying horses. Among the theories advanced to explain his win was the supposedly unlimited supply of milk and German
oats provided to French horses at the end of the Second World War. French experts however, pointed to the tendency of British breeders to undervalue stamina in pedigrees and place undue emphasis on sprinting and two-year-old races. Late in 1946, the American magazine
Time proposed an international championship race in which Souverain and the Australian champion
Bernborough would be matched against leading American runner
Stymie, but the event never came to fruition.
1947: four-year-old season As a four-year-old, Souverain won the older horses' version of the Prix Jean Prat (the race now called the
Prix Vicomtesse Vigier) at Longchamp in May. In June, he was sent to race in Britain for the second time, when he contested the
Gold Cup over two and a half miles at
Royal Ascot. He started at odds of 6/4 and won by four lengths from the other French challenger
Chanteur, who had been made odds-on favourite. The prize money of £11,316 made the race the most valuable ever run in Britain up to that time. Souverain returned to France in August and recorded his last important success when he won the Prix Kergorlay at
Deauville Racecourse. ==Assessment==