The ancestral origin of the Shiba Inu is the feral wolf. Despite its sunny disposition, the Shiba Inu directly rises from a very brutal and untamed bloodline, and still manages to retain some of the better wolf characteristics. The Japanese revere wolves and by way of bloodline association, they hold in high regard the Shiba Inu. Wolves fill Japanese legend and are depicted in positive way, hence the Shiba Inu being named a national treasure in 1936 by the Japanese.
The Shiba Inu, is the tiniest of the six main Japanese breeds, which immediately places him the same category as the Japanese wolf who was also quite small. Physically, the Shiba Inu resembles the wolf, with an almost triangular-shaped head, square body, and pointed muzzle, slanted upturned eyes, and pointed ears. They have double coats, with a straight outer coat and a smooth, heavy undercoat. They can carry a red coat similar to the on seen on the red fox who shares close kinship with the wolf.
The spirit of the Shiba Inu is of the wolf also. The Shiba Inu is extremely sociable and this is similar to the tribal instincts of the wolf. This trait in the dogs' bloodline is what makes it so easy to companion with human beings. Thus, mankind took advantage of that, making the dog a domesticated animal. The dog is basically a tamed wolf.
Japanese legends oftentimes featured wolves as positive protagonists, assisting people when they were in danger. This line of thinking is more keeping with what the wolf ultimately became in mankind's society, unlike the horror stories of werewolves in western culture.
But the wild behavior, the attack mode primitive wolves naturally had to retain, lies latent in the modern day Shiba Inu. Shiba Inu, one properly trained, is never in danger of attacking its owner. But he may go after a rabbit or deer if in its vicinity. It is just the basic instinct from long ago that may come out every now and then
The Japanese describe the Shiba Inu in three special terms: Ryosei Kan'i, and Soboku. Ryosei describes the loyalty and sunny, playful disposition most Shiba Inu have, which wolves surely had when they were not in defense or hunt mode. Kani means courage and fearlessness, the characteristic you will find a Shiba Inu draws from his ancient bloodline whenever he meets strangers. Soboku is the spontaneity that a Shiba Inu is sure to exhibit
The Shiba Inu is an incredibly docile and loyal companion, once trained. The wolf in him adds to his unpredictability and fierce sense of protection. A pet Shiba Inu is a bit of the wild brought into the home, making it better for it.