Database: Oyamazaki and Oil Production

On the right bank of the Yodo River, at the western end of Yamashiro Province (known as the battlefield where Akechi Mitsuhide fought Hashiba Hideyoshi following the assassination of Oda Nobunaga) Oyamazaki, or more commonly Yamazaki, was originally the headquarters of a commercial hub that held a monopoly on the distribution of the oil extracted from the perilla frutescens (egoma) seeds. The oil was used as a source of light and was in high demand for altars in shrines and temples. At Oyamazaki, merchants made offerings of oil to gain the protection of the Iwashimizu Hachiman Shrine across the Yodo River. Oil production in Oyamazaki increased due to its proximity to Kyoto, which was a major consumer. Additionally, the political and religious influence of the Iwashimizu Hachiman Shrine at the imperial court and the Muromachi Shogunate favored the merchants of Oyamazaki. They were given priority or exclusive rights at every step of the process, from purchasing and shipping the raw material, egoma, to selling the finished product. Trade reached its peak in the late 14th and middle 15th centuries. However, following the Ōnin War and the fall of the shogunate, new merchants from other regions began producing and selling egoma oil, which broke Oyamazaki's stranglehold on the market.