Outbreak of the Revolt of Gan'gyo (March 15, 878)

More than a half a century of peace came to an end in Gan'gyo 2 (878) as the Emishi of Ideha revolted from Yamato rule.  According to Fujiwara no Yasunori Den (Bibliography of Fujiwara no Yasunori),

"Akita Castle's governor Yoshimine and his companions did not hesitate to oppress and hoard everything, so that [the people] felt resentment, and anger and thus revolted."

This translated into the unfair treatment in trade transactions, and the imposition of heavy taxes on the subject Emishi population.

The war broke out on March 15. In the article found in Nihon Sandai Jitsuroku:

...Governor of Ideha Fujiwara no Ason Okiyo reported through the horse stations, "Emishi rose in rebellion. On [the] 15th of this month, Akita castle, and the district's buildings and houses in the suburbs were burned down. So we are defending ourselves by the peace guards and recruiting an army from the districts."

The following report was sent on March 17 and was received on March 29 in Kyoto. Emperor Yozei was only 11 years old, so the regent Fujiwara no Mototsune sent these orders to both the provinces of Ideha and Michinoku:

To Ideha:

I am aware of the report on the 17th of this month. The Emishi rose in rebellion, attacked and burned the castle and some villages. Dogs or sheep become mad and their nature changes to become violently evil.  If we do not subjugate them, what is the punishment? Plan soon to send strong troops and grip [the enemy's] throats. But now in farming season, people are cultivating and sowing.  I fear [that] people's work may be hindered if they are mobilized.  It is said that the superior strategy in war is to beat [the enemy's] planning, and a good general does not fight. You should pacify the frontier people through skillful strategy.  I send the Emperor's other order to Michinoku province.  If troop strength in your province is insufficient for suppression, quickly ask Michinoku province for reinforcements.  All barbarians change their minds from time to time.  Although they are guilty [of rebellion], the policy of the province was not good.  You should suspend the creation of conflict through appeasement.

To Michinoku:

I received Ideha province's report on the 17th of this month. The rebels rose, and attacked and burned the castle and villages. The two provinces are adjacent to each other, so [ the author Suzutayu cannot read here. Maybe it says, 'you can know well' ]. If you do not take precautions, you cannot react to emergencies. Increase police efforts to pacify your province.  If Ideha province needs reinforcements, send a strong force and help them in a timely manner. In war, swiftness is prized.  To not act is shameful. Don't wait until a request has been sent because the opportunity can be lost.

The messages were recorded as having been sent between the province of Ideha and the central goverment as written down in the Nihon Sandai Jitsuroku.  It is thought that the editors of this work took their material from government library records. We can generally rely on them because they don’t dress up facts, and is thus a welcome source for historians. However, the record is spotty because the coverage of frontier areas such as Ideha was not a central concern for them.  The book does not comment on the names of the leaders of the revolt or how they were organized, and stereotypical labels such as “barbarian" was used by the editors, who were themselves members of the aristocracy and government scribes. 

According to the archeologist Komatsu Masao we can find several different political and cultural areas around the revolt.  Akita Castle and its surroundings were predominantly Japanese in culture. Some dishes with the kanji character for 'barbarian' have been found from a site southeast of the castle.  This points to the likelihood that Emishi who were subjects lived here. However, the remains of settlements along the Noshiro river valley are filled with Emishi artifacts and points to those who lived semi-independently of Yamato. To call this conflict 'revolt' is only partially correct insofar as there were those Emishi who had been living as subjects of the Yamato government who subsequently turned against it, however, it was also a war against independent Emishi tribes who had never been subjects of Yamato.

The main trade article that the Emishi of Dewa desired also became central to the later Ainu of Hokkaido. The Emishi exchanged horses, slaves (unclear as to who these were), and animal pelts for iron and cloth.  Iron was and continued to be the central article that native peoples depended on. Typically this iron was in the form of swords and other iron tools. This seems to imply that these peoples did not produce iron themselves and thus depended on the Japanese for iron implements.  On the other side, the Japanese coveted the Emishi horses as well as fur pelts (1994:4). This trade was essential to both parties but like what happened to the American natives the trade became asymmetric in favor of the more developed societies. The revolt of 878 is tied to other similar revolts occurring for similar reasons that took place in later centuries between the Satsumon (pre-Ainu) and Japanese such as the Koshamain Rebellion of 1457. In fact, this similarity ties together the natives of northern Honshu to those of Hokkaido.

References:

Howell, David L.. "Ainu Ethnicity and the boundaries of the early modern Japanese state." Past & Present (February 1994).

Northern Tohoku and Tsugaru Emishi after the Conquest

Conquest of Emishi

2003.06.24 by Suzutayu (Kenjiro 2007.11.09, added links 2015.12.17)