Rikuō Province

Mutsu Province (陸奥国, Mutsu no kuni), officially called Rikuō Province (陸奥国, Rikuō no kuni) was an old province of Japan in the area of Iwate and Aomori prefecture.

It was also known as Ōshū (奥州) or Rikushū (陸州). In the Meiji era, the province was cut down to cover only present-day Aomori and given the new name Rikuō Province, which retained the original kanji.

On December 7, 1868 (January 19, 1869 in the Gregorian calendar), four additional provinces (Rikuchū, Rikuzen, Iwaki, and Iwashiro) were separated from Mutsu, leaving only a rump corresponding to today's Aomori Prefecture (with Ninohe District of Iwate Prefecture). At the same time, while the characters of the name were unchanged, the official reading was changed to the on'yomi version "Rikuō".

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