According to "Jiu Tang Shu" (Old Tang History) and "Shin To-jo" (New Book of Tang), the official history of China, the name of the country changed from `Wa' to `Japan' in the end of seventh century, from which it is assumed that there was a dynasty change during this period.
中国の正史『旧唐書』、『新唐書』の中で7世紀末に国号が「倭」から「日本」に国号が変わっているので、この時期に王朝が交代したと推定される。