Rikyu Hachimangu in Oyamazaki, Kyoto, founded in 859, is revered as the birthplace of Japan's oldest sesame oil production. In the medieval period, shrine attendants organized the Oyamazaki Oil Guild, wielding a nationwide monopoly over sesame oil backed by imperial and shogunal authority. This article examines that historical structure based on primary sources.

Founded in 859 by the monk Gyokyo, who enshrined the Hachiman deity brought from Usa Hachimangu, Rikyu Hachimangu stands as the direct predecessor of Iwashimizu Hachimangu. Seated on the site of Emperor Saga's Kayo Detached Palace, this ancient shrine at Yamazaki holds the key to understanding how Hachiman faith spread from Kyushu into the heart of the capital region.