Heiji Rebellion
Around 700 A.D., there is record of Emishi presenting local marine products at the Imperial Court, which may have encouraged immigration to the area. The area remained peaceful during the Nara period, due to the powerful influence of the Minamoto Clan. However, during the Heian Period, the Minamotos were defeated by Taira no Kiyomori in the Heiji Rebellion. The Kasai Clan received the region, but were left heirless near the end of the Azuchi-Momoyama period. After the Battle of Sekigahara in 1600, the area was given to Date Masamune as part of his lands.