Dewa Province

Dewa Province (出羽国, Dewa no kuni^?) was a province of Japan comprising modern-day Yamagata Prefecture and Akita Prefecture, except for the city of Kazuno and the town of Kosaka. Dewa bordered on Mutsu and Echigō Provinces. Its abbreviated form name was Ushū (羽州^?).

Prior to the Asuka period, Dewa was inhabited by Ainu or Emishi tribes, and was effectively outside of the control of the Yamato dynasty. Abe no Hirafu conquered the native Emishi tribes at what are now the cities of Akita and Noshiro in 658 and established a fort on the Mogami River. In 708 AD Dewa District (出羽郡, Dewa-gun^?) was created within Echigō Province. The area of Dewa District was roughly that of the modern Shōnai area of Yamagata Prefecture, and was gradually extended to the north as the Japanese pushed back the indigenous people of northern Honshū. Dewa District was promoted to the status of a province (Dewa Province (出羽国, Dewa no kuni^?)) in 712 AD, and gained Okitama and Mogami Districts, formerly part of Mutsu Province.

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