The ancestors of the Kai Ken originated in Japan a very long time ago, but detailed records about the dog's lineage have either been lost to time or perhaps kept under wraps in order to maintain the breed's superiority through secrecy. For hundreds or perhaps thousands of years, this breed was developed and kept in isolation due to the sea, mountains, and culture. The Kai Ken is believed to be the purest of the six native Japanese breeds.
With the encroachment of the world during and after WWI, the Kai nearly became an extinct tiger dog. In 1931, the Kai Ken Aigokai was founded. This club, which is best described as a preservation effort, helped start a breeding program to protect the dog from disappearing. During that decade, the first dog exhibition was held (1931), the dog was declared a monument by the nation (1933), and the breed was formally recognized by the Japanese Kennel Club (1934).
The preservation of the breed may not have occurred had it not been for the Kai Ken Aigokai's founder, Dasuke Adachi. After observing one of these rare hunting dogs in Kofu (a city in Japan), Adachi endeavored to find more of the dogs and to work to preserve the breed. The effort was an arduous one that required treks into the mountainous, somewhat hostile terrain where the dogs had lived for centuries. Adachi and his team persevered and returned with two dogs that he believed were the best to be found, and these two dogs were the foundation stock for the club. Adachi became the chairman, and the first dog show, called the Nihon Ken Hozonkai (NIPPO), was held that same year.
The club's efforts persuaded the Japanese government to help subsidize Kai Ken dog owners. To this day, the primary registry is the Kai Ken Aigokai that was started in 1931.
By the 1950s, some of the dogs had been taken to the United States, but it is believed those specimens didn't survive. Another attempt in the 1990s did succeed, prompting the AKC to take notice. While there are Kai Kens in the Western World, the breed remains extremely rare outside of Japan.
The Kai Ken was recognized by the FCI in 1982 and by the United Kennel Club (UKC) in 1997. The AKC placed the breed in its Foundation Stock Service in 1997.