河西における漢と匈奴の攻防：前漢後半期から後漢初期の史料分析を通じて

The research to date on the war between the Han Dynasty and the Xiongnu fought on a front running along the periphery of northeast China during the late Former Han period has historiographically centered around descriptions in the Shiji 史記 and Hanshu 漢書 with little attention being given to the Han-related wooden strip documents (hanjian 漢簡) unearthed in the northwest at Dunhuang 敦煌 and Juyan 居延. The present article is an attempt to correct this situation by using these latter documentary artifacts in examining the Han-Xiongnu war.First, the author collected items concerning the Han Dynasty’s defensive action against the Xiongnu invasion contained in the Juyan collection and analyzed them empirically, beginning with the task of dating them. He then compared the results with entries in the Hanshu concerning the war and came up with the following observations concerning how the war was fought on the northwest periphery at that time, especially in the Hexi 河西 region.To begin with, as a result of dating the war as described in the Juyan documents, it is clear that the fighting took place up through the middle of the Former Han Emperor Xuan’s reign (74-49 BC) and from the end of the Former Han into the early years of the Later Han period. There is no evidence in the Juyan documents of when a peace agreement was reached between the two belligerents, but it is clear that both parties strove to uphold the agreement. The author also estimates that a total of several thousand troops were involved in the fighting on both sides.Secondly, there are war-related Juyan documents that coincide well with similar items contained in the Hanshu, and the former seem to reflect what was written in the latter. However, from the reign of Former Han Emperor Zhao (87-74 BC), the Hanshu covers the war only on the Seiiki 西域, as if nothing was happening in the northwest, a situation that conflicts with the Juyan war documents. What this means is that from Zhao’s reign a Han line of defense was firmly established in the northwest thus minimizing losses due to the Xiongnu invasion there. The northwestern front thus became relatively quiet compared to the struggle for power raging on the Seiiki 西域; so the compilers of the Hanshu must have decided to edit items about the northwestern front from the chronicle.As a result of his empirical study, the author firmly establishes the existence of content in the Dunhuang and Juyan Han-period wooden document collections corresponding to items appearing in the Hanshu; and concerning the investigation of the Han-Xiongnu war, he has proven the necessity of utilizing the Dunhuang / Juyan collections to complement and augment the descriptions contained in the chronicles of the period. As a result of this study, another clue has been discovered in clarifying the real conditions on the northwest periphery and that region’s historical development during the Han period through consolidating information contained in the Dunhuang / Juyan collections with the large amount of facts researchers have already discovered from other sources about such subjects as administrative and military institutions.