The Ainu Dog is a Japanese Spitz breed rarely seen outside that county. The dog was named after the Ainu tribe. Origin is unknown. They arrived in Japan over 3,000 years ago when the Ainu brought this Spitz-type dog with them. As the Ainu were pushed onto the island of Hokkaido by an influx of Japanese people, their dogs gradually became restricted to this island. The dog's ever alert and suspicious nature lent itself to the required role of village guardian. Their dog has changed little over the centuries. The Ainu Dog is probably the oldest of the Japanese breeds. It was later named the Hokkaido Dog, but is still better known as the Ainu Dog; indeed it is registered with the FCI under that name. Many Ainu Dogs have blue-black tongues, a physical trait that suggests a distant relationship with the similarly tongued Chow Chow and Chinese Shar Pei. Through the active work of the Society For The Preservation of Japanese Breeds, the Ainu Dog was designated a Japanese Natural Monument in 1937. The Ainu Dog has always distinguished itself in big-game hunting (especially bears), in guarding property, and as a draft animal.

The Ainu Dog is a thin, muscular, sturdy-looking dog. It is impulsive and fast and has a light gait. Ainu's have small, erect ears that are at a right angle to the brow. Its eyes are somewhat small, dark brown and set triangularly. The teeth are healthy, solid and non-protruding. Some have spots of black on their tongues. The bridge is straight leading to its dark nose. The well-fitted lips have dark pigmentation. The tail curls in typical Spitz fashion. The Forelegs are straight and lean and the hindquarters are covered with a double coat. The harsh, straight coat colors come in sesame, brindle, wolf gray, red, brown or white.

When the Ainu tribe arrived in Japan nearly 3,000 years ago, they had dogs of Nordic type with them, and these became the Ainu Dog. The Ainus were an ancient people who migrated to and were the first settlers in Japan, ten centuries before Christ. They were a white race of unknown origin, and at one time lived on all the islands of Japan.

The Ainus were slowly pushed out over the centuries by the influx of Yamato (Japanese) people and now live only in their own settlements on the northernmost island of Hokkaido. (They live in their own groups, with their own separate and quite primitive culture.) Their dog has changed little over the centuries. The Ainu Dog is probably the oldest of the Japanese breeds and may have been altered somewhat through crosses with matagi dogs.

The breed is known for its strength and was a draft dog originally, but is used today for hunting and guarding. The Ainu Dog is extremely courageous for his size, willingly attacking a 650-pound bear. He is generally kept in the home.

As is common with most of the Japanese breeds, this dog is clean and mannerly yet quite ready to warn of danger. As a working dog for so long, he tends to be a bit coarser and more primitive than the other Japanese breeds. His character is sharp and fearless. He also differs by having smaller ears, a broader head and a fiercer expression. Also of interest is that, although not particularly desired, these dogs occasionally have the black tongue. This may hint at ties to the Chow Chow and mainland China. If loved and cared for, he is said to be obedient to his master and an irreplaceable friend.