Ainu – The largest indigenous population of Japan, descending from ancestors who migrated there around 10,000 years ago. The Ainu mainly live in the northern islands of what is now Japan, especially Hokkaido and the Tsugaru Strait area, although in the past they inhabited a wider area and their population was larger. Ainu scholar Sakurako Tanaka distinguishes between ancestral shamans and contemporary mediums, tuskur. She traces this “decline” to the 17thcentury distinction between male ceremonial leaders and female mediums. Tanaka argues that while some mediums have animal kin, manipulate animal spirits, and lead communal ceremonies, rites, and even political confrontation with outside authorities, they can be distinguished from shamans because they do not exhibit mastery of spirits but become possessed by them. The passivity of the medium allows powerful other-than-human persons, kamuy, and ancestral souls who had elected her to reside in her and provide knowledge of the other world, taboos, and medicinal herbs and therefore to diagnose and heal illnesses while in an altered state of consciousness or trance. In recording the skill and knowledge of particular Ainu mediums, Tanaka casts doubt on the value of too strong a distinction between shamans and mediums: the precise nature of human relationships with powerful other-than-human persons varies not only from individual to individual but also according to cultural expectations. If more weight is placed on the choices made by shamans’ helpers and on the roles played by shamans in their communities, it becomes increasingly difficult to insist that possession and trance are distinct.