貴霜丘就却の歿年

Abstract

This paper attempts to shed new light on the early history of the Kushan Empire through fresh interpretation of the Chinese literature of the time. It first argues that the Kushans did not share the same origin with the Da Yuezhi, as previously thought, by examining the nature of xihou (翕侯), a term which appears in the Hanshu's accounts of the Wusun, the Kangjiu, and the Da Yuezhi. Careful scrutiny of the references to the xihou in its accounts of the Wusun in particular reveals that the xihou is a status of highly political significance, with which the kings of the nomadic empires of the area often endowed local oasis rulers, suggesting that the xihous were not kin to the nomadic people but native to the areas they invaded. The Hanshu mentions that the 'five xihous', including the Kushan xihou, belonged to the Da Yuezhi. The Kushan xihou ruled over western Wākhān in Tokhāra and played an important economic role from the first half of the first century BCE onwards in the trade between the Han court and the Da Yuezhi. The Kushans' commerce area seems to also have extended southwards ; for the Da Yuezhi's placement of another xihou called Shuangmi suggests a significant caravan route leading southwards to Gandhāra and connecting to the vast international commerce area attested in Periplus Maris Erythraei ; and Shuangmi's governing area is adjacent only to that of the Kushan xihou. The wealth brought forth by such large-scale trade, both eastward and southward, I argue, was an important factor that enabled Qiujiu Que, the last Kushan xihou, to achieve political independence from the Da Yuezhi. Considering the Hanshu's allusion to Zhangqian's visit of the Da Yuezhi in 129 BCE and the Hou Hanshu's reference to Qiujiu Que's independence, together with the wood slip document dated 37 BCE, recently found at the archaeological site of a Han official station near Dunhuang, it can be deduced that his independence was achieved in the period between 36 and 30 BCE (most probably in 35 BCE). This observation gives us not only an important insight of the early history of the Kushan Empire, but also a significant clue for solving the long-debated issue of the accession year of Kanishka I, Qiujiu Que's great grandson. At the time of the independence (around 35 BCE), Qiujiu Que must have been mature in age, presumably older than 15 years old. Considering this with the Hou Hanshu's reference to his demise at the age of over eighty, he must have died earlier than in CE 30. Then, unless the periods of the reigns of the successive kings Vima Taktu and Vima Kadphises (father and son) were both extremely long, which is quite unlikely, it would be reasonable to conclude that Kanishka I was enthroned in CE 78, rather than in CE 127.