It was completed before the early Kamakura period, and the form of the character suggests that it was probably made at the end of the Heian period, so this is regarded as the earliest old genealogy among the existing ones.
成立時期は鎌倉時代初期を下らない時期で、おそらく字体などから平安末と見られる、現存するものの中では最も古いと見られる古系図である。