The Tosa Inu is also known as the Tosa Fighting Dog, Tosa-Ken, Tosa-Token, and Japanese Mastiff. Developed in the 1800's to compete in dog fighting rings in Japan, the breed is now used primarily as a guardian and is proving itself as a working dog. The Tosa Inu is a well-muscled, solid dog, reaching 24-26" and up to 200 pounds. It has a short, dense coat. Stoic, relentless, and courageous, it may be aggressive toward people and animals. Official recognition: FCI Group 2, CKC Group 8 - Miscellaneous Class.