The Izumo Kokuso are the hereditary high-priest family of Izumo Taisha, the oldest continuous priestly lineage in Japan. By ancient custom, when the office passed to a new generation, the Hitsugi Shinji (fire-succession rite) was conducted at the Sankaden hall of this shrine: the new Kokuso would bring back fire kindled here and use it to cook his first sacred offering, thereby succeeding to the office. This tradition, in which Kumano Taisha served as the core of the Izumo Kokuso investiture ritual, has continued since antiquity.