何處是居延？－居延城建置反映的漢代河西經營進程

1930年代中瑞西北科學考察團調查額濟納河（古稱弱水）流域諸遺址以來，漢代「居延城」為哪座遺址的問題，始終爭訟不休。《漢書．地理志》載都尉治所在居延縣城，但作為「內證」的居延漢簡卻顯示兩者異處。過去學者透過傳世文獻、出土材料和遺址資訊，標定「居延城」址，但引用相同簡文卻得出不同的結論，對「居延城」、居延縣城、都尉府三者的關係也未有共識。本文試圖以動態的視角重新梳理漢代開拓河西邊地的歷程，以此為基礎解釋簡文與傳世文獻記載相左、簡文內部記載相異的原因。第二節重新分析簡牘材料，區辨其性質。第三節考訂張掖立郡的時間，兼論河西地區整體的拓展，作為瞭解居延地區建置過程的前提。第四節接著探討「居延」一詞涵義的多樣性、「居延」地名的移動與範圍的變遷，以及「居延」建置的過程。第五節說明居延地區在漢代河西行政區劃上的更易，討論從「居延都尉區」到「張掖郡居延縣」的變化、都尉及其治所的沿革、「城」的多重意涵與弱水河道的管控等課題。最後總結上述討論，嘗試指出居延地區起初作為「都尉區」的特殊性，並以居延地區的開發為例，呈現漢朝在河西地區拓展過程中不同階段的舉措與進展，作為漢朝對外擴張步驟的一種參照。

關鍵字

河西經營；居延城；居延都尉；都尉區；行政區劃

並列摘要

Ever since the 1930 Swedish-Chinese joint scientific expedition to the northwestern provinces of China surveyed various archeological sites along the Ejina River (called the Ruo River in ancient times), determining location of the Han Dynasty city of Juyan has been very contentious. The Hanshu Dilizhi records that the capital of Du-wei was in Juyan county town, but Juyan's Han Dynasty wooden and bamboo Slips indicate a different location. Previously, scholars have marked the site of Juyan City according to ancient literature, excavated material and information from archeological sites. Nevertheless, they not only drew different conclusions from the same slip texts, but also did not reach a consensus on relationships between Juyan City, Juyan county town, and the capital of Du-wei.This paper attempts to use a dynamic perspective to explore the history of the Han Dynasty's development in the Hexi region. It will use this history as a basis for explaining the conflicts between the slip texts and ancient literatures as well as the internal contradictions contained in the slip texts themselves. The second chapter reanalyses the bamboo and wooden slip texts in order to differentiate them by kind. The third chapter investigates the time when Zhangyi was established and discusses the expansion of the overall Hexi region in order to comprehend the development of the administration of the Juyan region. The fourth chapter then discusses the diverse meanings of ＂Juyan,＂ the moving location of the place name ＂Juyan＂ and the changing scope of the region called ＂Juyan,＂ as well as the development of the administration of ＂Juyan.＂ The fifth chapter explains the changes to the Juyan region with regard to the administrative division of the Hexi region during the Han Dynasty and discusses the transition from ＂Juyan Du-wei District＂ to ＂Zhangyi Juyan County.＂ It then details, the history of Du-wei and its capital, the multiple meanings of ＂city,＂ the control of Ruo River watercourse and other topics. Finally, I will summarize the above points of discussion, and using the Juyan region as an example, indicate the particular characteristics of the ＂Du-wei District＂ in the early expansion of the Han frontier. The results of the study reveal the different stages of the process of development in the Hexi region during the Han Dynasty and indicate that the external expansion of the Han Dynasty was carried out in stages.