The Yamato period (大和時代, Yamato-jidai) is the period of Japanese history when the Imperial court ruled from modern-day Nara Prefecture, then known as Yamato Province.. While conventionally assigned to the period 250–710, including both the Kofun period (c. 250 –538) and the Asuka period (538–710), the actual start of Yamato rule [] is disputed.