The scrolls are known for containing supplementary records concerning the mythological age, complementing the Kojiki and the Nihon Shoki, the two major ancient documents in Japan.
Gulungan-gulungan itu diketahui mengandung catatan tambahan menyangkut zaman mitologi, melengkapi Kojiki dan Nihon Shoki, dua dokumen kuno terkemuka di Jepang.