Northern Fujiwara
During the Yayoi period, the area that would become Aomori Prefecture was impacted by the migration of settlers from continental Asia to a lesser extent than the rest of Japan to the south and west of the region. The region, known then as Michinoku, was inhabited by the Emishi. It is not clear if the Emishi were the descendants of the Jōmon people, a group of the Ainu people, or if both the Ainu and Emishi were descended from the Jōmon people. The northernmost tribe of the Emishi that inhabited what would become Aomori Prefecture was known as the Tsugaru. Historic records mention a series of destructive eruptions in 917 from the volcano at Lake Towada. The eruptive activity peaked on 17 August. Throughout the Heian period the Emishi were slowly subdued by the Imperial Court in Kyoto before being incorporated into Mutsu Province by the Northern Fujiwara around 1094. The Northern Fujiwara set up the port settlement Tosaminato in present-day Goshogawara to develop trade between their lands, Kyoto, and continental Asia. The Northern Fujiwara were deposed in 1189 by Minamoto no Yoritomo who would go on to establish the Kamakura shogunate.