 The Yamato government constructed the Nakoso barrier around 708 AD against possible invasion by the Emishi tribes in the north.In the late 11th century, the Iwaki clan (岩城氏) of Hitachi Province invaded Iwaki district (磐城郡) and divided it into four districts of Yoshima, Iwasaki, Iwaki, Naraha.The clan ruled the area from the Kamakura period to the end of the Sengoku period.