Shapeshifting foxes of Japanese legend, growing wiser and more powerful with every tail.
Documented
Inari's own messengers
Foxes attach to the worship of Inari, the rice deity, by at least the Heian period. Shrine records, tale collections like the Konjaku Monogatari, and votive statues all document the fox as a sacred intermediary long before it became a cartoon.
Assessment: Documented in shrine tradition and Heian literature. The sacred fox is old, the cute fox is recent.
Stories
Nine tails and fox possession
The stories say a fox grows a tail per century, that kitsunebi fox-fires drift over fields at night, and that a possessed person, kitsunetsuki, must be exorcised or the fox starved out. Fear and fascination ran in the same channel.
Assessment: Folklore in the strict sense: widely told, locally believed, never verified. The possession diagnosis says more about the doctors than the foxes.
Interesting claims
A foreign fox in native dress
The claim: Japan's fox lore is a local fork of China's huli jing and Korea's kumiho, imported along trade routes and Buddhist texts and rebranded as Inari's servant.
Assessment: Influence across East Asia is documented and expected. A wholesale imported origin erases the shrine record. The fox likely had more than one passport.
Sources and further reading
Karen Smyers, The Fox and the Jewel: Shared and Private Meanings in Japanese Inari Worship (1999)
Konjaku Monogatari, fox tales, Heian period
Nozaki, Kitsune: Japan's Fox of Mystery, Romance and Humor
Kojiki and Nihon Shoki, fox motifs
Worth asking
A people trusted a known liar to carry their prayers. What does that say about what they thought of their gods?