The Prix de Diane, the French Oaks, was first run at Chantilly on 18th May 1843 over 2100 metres when won by Nativa, owned by Prince Marc de Beauvau, trained by Henry Jennings and ridden by Tom Jennings. For over a century it was restricted to horses born and bred in France, and that did not change until 1946. In 1848 it had to be run at Versailles because of the Revolution, and had to be cancelled altogether in 1871 due to the ongoing Franco-Prussian War. Unusually, there has never been a dead-heat to date, although there have been many short-head wins. During the First World War the race was abandoned between 1915 and 1918, while the 1919 and 1920 races were held at Longchamp, although the race then returned to its traditional home, Chantilly, in 1921. As a one-off, it was held at Longchamp again in 1936. During the Second World War the 1940 race was not staged, and the 1941 and 1942 editions were held at Longchamp, but with the continuation of the War the races in 1943 and 1944 were staged at Le Tremblay, albeit over 2150 metres. Between 1945 and 1947, the years after the War, the race was held at Longchamp, with the 1946 edition being especially important as it was opened to non-French trained or bred horses for the first time. However, it was a further 24 years before Sweet Mimosa won in 1970 to claim the title of first non-French filly to win the Oaks. Just two fillies, Fille de L'Air in 1864 and Pawneese in 1976, have completed the English and French Oaks double, while 6 French Oaks winners have gone on to win the Prix de L'Arc de Triomphe, the most recent to date being Treve in 2013.