Russian Blue
In the late 1950s, the Persian was used as an outcross by some American Shorthair breeders. This was done in secret in order to improve their body type, and crosses were also made with the Russian Blue and the Burmese. The crossbreed look gained recognition in the show ring, but unhappy American Shorthair breeders successfully produced a new breed standard that would disqualify American Shorthairs that showed signs of crossbreeding. One American Shorthair breeder who saw the potential of the Persian/American Shorthair cross proposed and eventually got the Cat Fanciers' Association judge and American Shorthair breeder Jane Martinke to recognize them as a new breed in 1966, under the name Exotic Shorthair. In 1987, the Cat Fanciers' Association closed the Exotic to shorthair outcrosses, leaving Persian as the only allowable outcross breed.