契丹の旧渤海領統治と東丹国の構造 : 「耶律羽之墓誌」をてがかりに The Kitai Dynasty's governance of Bohai and the structure of Dongdanguo as seen from Yelu-Yuzu's Epitaph
It was in 926 AD that Bohai was conquered by Yelu-Abaozhi 耶律阿保機, founder of the Kitai 契丹 (Liao 遼) Dynasty and was designated as Dongdanguo 東丹国. There were many aspects of Dongdanguo that had escaped researchers until 1992, when the inscribed epitaph of Yelu-Yuzu 耶律羽之 was discovered. In this article, the author first investigates the genealogy contained in the inscription and concludes that the leaders of Yelu Abaozhi's tribe (迭剌部 Dielabu) participated in the governance of Dongdanguo. At that time, the Dielabu had been broken up in order to control its burgeoning power over the other seven tribes, necessitating a redistribution of land and people for the purpose of herding. Dongdanguo was established by allocating authority over Bohai to such members of the Dielabu as the brothers of Yelu-Yuzu. In other words, in the background of the establishment of Dongdanguo there lay not only the problem of governing the former subjects of Bohai, but also the aspect of a nomadic state distributing land and human resources among its members. Secondly, the author puts the bureaucratic chaos of Dongdanguo described in the existing source materials into better perspective based on the inscription. Here, the former bureaucratic system of Bohai, with such offices as Daneixiang 大内相, was not only kept in tact to govern Bohai, but was also instituted as a means for organizing Kitai tribes ; that is, adapted to Kitai society itself. Finally, concerning the reason for moving the capital of Eastern Kitai to Liaoyan 遼陽, the inscription shows that king of Kitai was involved in a decision based on the proximity of Liaoyan to the territory controlled by the Dielabu, rather than the conventional explanation that the move was motivated by the desire to monitor the activities of Yelu-tuyu 耶律突欲, the king of Dongdanguo. There is also the view in the research to date that Dongdanguo did not in fact exist, but the discovery of the inscription clearly shows that Dongdanguo was incorporated into the ruling class of Kitai tribal politics, adapted to its nomadic society and was a functioning polity.
史学雑誌 117(6), 1097-1122, 2008