<論説>澶淵の盟の歴史的背景 : 雲中の会盟から澶淵の盟へ

Abstract

本稿は、契丹(遼) と北宋の間で一○〇四年に結ばれた、いわゆる澶淵の盟の歴史的背景について検討し、盟の性格について考察するものである。 具体的には、まず澶淵の盟における規定あるいは盟後の両国関係において特徴的と考えられる諸点について、いずれも契丹と五代王朝の間ですでに同様な関係が見られたことを確認する。 次に、澶淵の盟が契丹と後晋の関係と相似のものであり、さらに耶律阿保機と李克用の間で結ばれた「雲中の会盟」にまで遡りうることを論証する。 以上を中央ユーラシア史の観点から位置づけたとき、澶淵の盟をウイグル帝国の崩壊後における混乱の帰結と見なしうると結論する。

Prefacing my main argument, I point out that among the Five Dynasties, only the Later Liang differed in origin from the other four later dynasties, the Later Tang, Later Jin, Later Han and Later Zhou. These latter four dynasties were established by the Shatuo and were derived from the so-called Li Jin. Another important fact is that Song dynasty was closely linked to the later four dynasties. First, in order to accumulate evidence concerning the sources of the treaty of Chan-yuan, I examined the following three unique characteristics of the treaty and its aftermath in the context of the diplomatic relations between Khitai and the Five Dynasties. 1) Annual tribute payments Both the Later Jin and the Northern Han paid annual tribute to Khitai. Moreover, this idea had already emerged from, at least, in the end of Later Tang. 2) Fictitious kinship between emperors After the bonds of fictive brotherhood were tied between Ye-lu A-bao-ji and Li Ke-yong, all the emperors of Khitai formed fictitious kinship relations with emperors of the Later Tang, Later Jin, or Northern Han. 3) Mutual use of the terms northern dynasty and southern dynasty Since the founding of the Later Jin, such designations had been used, especially in oral communications. As a result of this examination, it is apparent that several points that have been regarded as unique to the Chan-yuan regime were not in fact entirely new at that time. At the same time, it can be pointed out that these were not issues in the relationship between Khitai and the Later Liang. I next considered the diplomatic relation between Khitai and the dynasties of northern China before the treaty of Chan-yuan, and confirmed these historical facts. 1) The treaty of Chan-yuan was concluded on the basis of the diplomatic relations between Khitai and the Song dynasty in the 970s. 2) Diplomatic relations between Khitai and the northern Chinese dynasties, Northern Han, Later Zhou and Later Han (the latter two ended in failure) and including the relationship between Khitai and Song dynasty in 970, were all initiated due to Khitai, seeking a successor for Shi Jing-tang of the Later Jin. 3) Comparing the relationships in the treaty of Chan-yuan and that between Khitai and the Later Jin, one sees that they are similar in most respects. 4) Shi Jing-tang succeeded to the throne as the successor of Li Si-Yuan not only in domestic terms but also in terms of external relations, and therefore the relationship between Khitai and the Later Jin was linked to the relationship between Khitai and later Tang, and also to Li Jin. As the result of this analysis, it can be said that the treaty of Chan-yuan was a reincarnation of the relationship between Khitai and the Later Jin (Shi Jing-tang), and that its source can be found in the treaty of Yun-zhong concluded between Ye-lu A-bao-ji and Li Ke-yong, namely Khitai and the Shatuo. Furthermore, the idea that the treaty of Chan-yuan was a rarity or anomalous in terms of the relationship between a Chinese empire and its neighbor must be revised. I concluded that from the viewpoint of central Eurasian history, because both Khitai and the Shatuo were situated on the fringe of the Uighur empire and started to develop after its collapse, the treaty of Chan-yuan marks the end of a historical trend following the collapse of the Uighur empire.