History books such as "Kunitsufumi" (National Record), "Sumeramikotonofumi" (Record of the Emperors), which were to be handed down by the imperial family for generations, were possessed by the Soga clan and were retained at the residence of the Soga clan.
『国記』（くにつふみ）・『天皇記』（すめらみことのふみ）と言った皇室が代々受け継ぐべき史書を蘇我氏が所持し邸宅で保管していた。