This system was established on October 14, 826 based on sojo (report to the Emperor) made by KIYOHARA no Natsuno ("Ruiju Sandaikyaku": Shinno-ningoku Daijokanpu (the official document issued by Daijokan, Grand Council of the state)). |
天長3年9月6日 (旧暦)(826年10月10日)、清原夏野の奏上に基づき制定された(『類聚三代格』:親王任国太政官符)。 |