Complex sentence: According to the "Kojiki" (712) and "Nihon Shoki" (720), Buretsu died without a successor, at which time a fifth generation grandson of Emperor Ōjin, Keitai, came and ascended the throne.
Split into simpler sentences: According to the "Kojiki" (712) and "Nihon Shoki" (720), Buretsu died without a successor. At which time, a fifth generation grandson of Emperor Ōjin, Keitai, came and ascended the throne.