Northern Tohoku and Tsugaru Emishi after the Conquest
During the post conquest period the Emishi who were not conquered further north continued to pose problems for the Japanese state, but there was little the latter could do. Exhausted from a century of war the state was itself unable to justify a further push northward due to the diminishing returns of such an invasion, and the difficulties of holding onto the territory north of what is now Morioka. The invasion of the Tohoku and the conquest of the Isawa Emishi took a considerable amount of time and resources and even after the conquest holding onto the gains and administering the territory was all the government could do. The Emishi did not disappear suddenly after 811 when the Japanese army was victorious under Sakanoue no Tamuramaro, but they too changed their approach to the Japanese state. The Tsugaru Emishi became the most powerful group in the post conquest period. Many northern Emishi left beyond the frontier became fushu (Emishi allies) and instead of fighting against the Japanese fought amongst themselves and against the Watarito (Hokkaido) Emishi in the ninth century.
There were a number of reasons that held the Japanese state back after the conquest of the Tohoku. The most important of these reasons was the lack of Japanese migrants in the area north of present day Morioka, and unlike the wide Sendai and Kitakami plains the northern regions were heavily forested and mountainous not easily amenable to agricultural development. The Tsugaru area corresponding to northern Aomori prefecture was a natural gateway to Hokkaido and was an important transitional area where trade relations between Japan and the Emishi of Hokkaido took place. The Emishi who lived here were mainly epi-Jomon with some admixture of Kofun transplants, but by and large formed the group that in time became the Ezo of the medieval period. These people were of the same group who later became the ancestors of the Satsumon culture, the formative culture of the Ainu, in Hokkaido without question (1).
These are the same Emishi who were mentioned by the Japanese envoy to Emperor Tai-Tsung in 659 in the Nihon shoki as one of three Emishi groups. Even at this early date they are mentioned as tsugaru emishi. This goes back to the question of who these people were and why the mention of them at that time is important. None of these sources makes a distinction that the Emishi were from different peoples. These writers did not make the kinds of distinctions made by modern scholars. It isn't that ancient writers were less perceptive but rather the opposite: if there was a distinction they would have made it like they did with the Ashihase (or Mishihase). The only distinction they made about them is that they were of three groups: nigi emishi, arai emishi, and tsugaru emishi (translated: gentle emishi, rough emishi and emishi from the Tsugaru peninsula). Further understanding of the ancient writers and what they meant by these terms is allied Emishi, enemy Emishi and Tsugaru Emishi. At that time the Tsugaru peninsula (watarito or southern Hokkaido was included) was the farthest known geographical region where they knew the Emishi lived. They were seen not as various rebel groups but as a particular people.
It is indeed one of the mysteries that at this point cannot be resolved between the historical record and modern physical anthropology which my diagram summarizes. The Tsugaru Emishi is no exception to this: they are not seen as a separate people from the Tohoku Emishi. They are seen as outside the existing boundaries of the state just like other Emishi, and no mention of them as being different from other Emishi is seen. On the contrary, they are the continuation of the same frontier people who they fought in the Sendai plain. In contradiction to this, most modern scholars see the Tsugaru Emishi as the same ethnic group as the Emishi who lived in Hokkaido, but not the same as the Tohoku Emishi. Why is it that contemporary people saw them as the same people but modern scholars see them as separate? That is the key question that I have attempted to answer, but still eludes full explanation.
In the latter half of the ninth century there were clashes between the fushu (Emishi allies) living in the northern Tohoku and the iteki (Emishi barbarian enemies) of Hokkaido, and much fighting post Conquest occurred between the Emishi fushu in the northern Tohoku in what is today northern Iwate, northern Akita and Aomori prefectures. In these areas a number of hilltop forts have been found from this time period, and are attributed to the Emishi who built these forts for protection, a testament to the constant strife that characterized their society at that time (Kudo 2005:181-97). The map to the right shows the known locations (Kudo 2005:205) where the hilltop forts have been excavated. They seem to cluster north of Shiwa (marked by a square). This is where Shiwa castle was built by Sakanoue no Tamuramaro after the subjugation of the Isawa Emishi. This is also the area where present day Morioka is located. The red line represents (roughly) where the frontier stood in 811 after the defeat of the Isawa Emishi, but in reality Japanese control stopped approximately north of where both Shiwa and Akita castles were located. North of this area the Emishi were left alone most of the time as long as they did not attack the Japanese and declared themselves to be fushu. However, this did not prevent them from fighting against each other to control the trade between Japan and Hokkaido. Notice that the hilltop forts seem to be clustered near rivers in the mountainous interior and along the coast in the Tsugaru.
The most spectacular find is at the Hayashi no mae 林ノ前遺跡 site (in present day Hachinohe) where the remains of a battle that took place sometime between the end of the tenth to beginning of the eleventh century was discovered. Though the time period when forts were built started in the last half of the ninth century, it was not until this discovery when the true nature of fort society was revealed. What made this site unlike others was not just the remains of post holes and dwellings of the type associated with the epi-Jomon culture (kenketsu jukyou), but horse bones were scattered in areas of the site as were metal horse equipment. There were also ten human skeletal remains that were recovered in unusual places. These remains were not buried in the usual manner and may have died in situ, and a few showed possible signs of torture before being killed. In addition six buried skulls have been found. There maybe differing accounts of what occurred, but what is beyond doubt is that there was a severe battle that took place here, and the aftermath was messy and inconclusive. No victor emerged here to clean-up the site and provide proper burial as if the site was abandoned after the battle and left until it was discovered.
This battle was between the Emishi fighting amongst themselves in areas well north of the areas the Japanese controlled in the ninth and tenth centuries. What would cause such severe and merciless battles to be fought between the Emishi? What replaced the battles between the Japanese and the Emishi for control over the Tohoku was replaced in the late ninth century by battles between the Emishi themselves for control over the trade between Emishi territory and Japan. Though fighting with the Japanese state like what happened in the Gangyo revolt occurred occasionally most of the endemic fighting was internal. The trade that was prominent before the Conquest was still lucrative to any who could control its sources. Just like the fur trade that decimated the North American continent and militarized the native tribes that lead to the destructive campaigns by the Iroquois against Great Lakes tribes in the seventeenth and eighteenth centuries the story for the Emishi was similar. The fur trade just as in North America caused a great deal of dislocation among the native Emishi who lived in its shadow. Ostensibly the Emishi living outside the frontier after the Conquest became fushu (allies) of the Japanese state.
Though they were fushu they fought against each other for control over the trade goods and routes to the Japanese controlled areas of the Tohoku. On the Japanese side, people like Fujiwara Shigezane, controlled access to the trade to supply nobles with Emishi trade goods, especially in animal furs (seal and bear), gold and horses that were coveted by the Japanese. He was the son of Fujiwara Okiyo who was the governor of Ideha during the Gangyo uprising of the late ninth century based in Akita castle. This latter post was key for his son to receive favorable status at Akita castle where there was constant contact with Emishi and Japanese traders living near the castle who had contact with Emishi traders living beyond the frontier. Akita castle was favorably placed for the san-tan trade where furs could come from as far away as northern Hokkaido and the Sakhalin islands and exchanged hands through Amur peoples to Emishi from Hokkaido, south to the Tsugaru Emishi, and then to the fushu and to the Japanese. It was an asymmetrical trade like most trade with native peoples that creates dependence on manufactured goods from metal tools and weapons and rice to sake from the Japanese that either could not or were not created locally which the Emishi became dependent on in exchange for a finite resource in animal pelts. As local supplies became exhausted by over hunting further sources were exploited which lead to more conflicts between the Emishi living beyond the frontier (Kudo 2005: 176-88).
The threat of war from the north especially affected the northern Emishi as they became a buffer zone between Hokkaido and Japanese territory in the ninth century. In AD 875 the Watarito (Hokkaido) Emishi threatened Akita and Akumi-gun using eighty ships carrying a very large but unknown number of warriors. The Emishi of Akita apparently fought them off. In 879 the Watarito Emishi with over three-thousand men advanced towards Akita, but there is no record about the results of this incursion. In 893 another incursion of the Hokkaido Emishi was countered by the fushu of the northern frontier which resulted in a stalemate (Kudo 2005: 180-81). Most important about these records from the ninth century is the gradual but steady assimilation of unconquered and previously independent Emishi as allies of the Japanese state to the point where the interests of their alliance superseded ethnic or cultural ties with the Emishi of Hokkaido with whom they fought. Of course this was largely motivated by self-interest as the Tsugaru and Akita Emishi wanted control over the trade for which they fought with each other over, and certainly did not want the Emishi of Hokkaido controlling. The beginnings of the separation of the Emishi between northern Honshu and Hokkaido can be seen here.
1. There maybe controversy about the ethnic make-up of the Emishi of the Tohoku before and during the conquest of the eighth century, but virtually all scholars modern and before the war identify the Tsugaru Emishi with the Hokkaido Emishi, ancestors of the the Ezo and`modern Ainu.
工藤雅樹 Kudo Masaki, 古代蝦夷の英雄時代 Kodai Emishi no eiyu jidai (The Heroic Age of the Ancient Emishi). Tokyo: Heibonsha 2005.
Kenjiro Hakomori 2016.1.5 (edited 2018.12.6)