It was also mentioned in "Nihonshoki" that Emperor Nintoku started the palace in Naniwa during the Kofun period (the Tumuli period), and Emperor Kotoku established Naniwa no Nagara no Toyosaki no Miya Palace in the Asuka period.
古墳時代には仁徳天皇が最初に難波に宮を置いたとする伝承があり（『日本書紀』）、飛鳥時代には孝徳天皇が難波長柄豊崎宮を設けた。