Archaeological Research on Yuryakucho Era (later 5th century)

本课题的目的是分析百合草时代（公元5世纪以后）的社会变迁<th>，这一时期被认为是日本中部诸岛古代国家形成的重要时期。为了实现这一目标，调查人员对钥匙孔形土丘的分布和变迁进行了调查，重点是被认为代表吉备地区地方主血统的一系列墓葬。调查人员发现，在有屋久町时代，许多地区都出现了钥匙孔形墓葬等地方主血统，而中部地区的筑山、筑山等雄伟的坟堆则消失了。这表明，每个地方社区开始投资他们的劳动主要埋葬。调查者认为这并不意味着吉备地区的社区或首领的衰落，而是这一时期社会中土丘的意义发生了变化。为了证实这一点，调查者挖掘了马比町的天居山古墓，发现了许多有助于确定该墓年代的物品。并揭示了这种变化包括了受朝鲜半岛影响的墓室类型的转变，因此，研究者认为，从考古学的角度来看，有屋町时代应该被看作是一个长期的社会文化变迁，而不是剧烈的政治变革。

This project aimed to analyze the social transition during the Yuryakucho era (later 5^<th> century A.D.), which is thought to be an great epoch toward the formation of archaic state in central Japanese archipelago.To archive the goal, the investigators examined the distribution and transition of keyhole shaped burial mounds, focusing on the series of them which are thought to represent local chiefly lineages in Kibi district.The investigators revealed that, locul chiefly lineages included keyhole shaped tumulus appear in many areas during Yuryakucho era, while the majestic burial mounds as Tsukuriyama (Zozan) and Tsukuriyama (Sakuzan) disappeared in central area. This indicates that each local community began to invest their labor for chiefly burials. The investigator declares that it is not interpreted to be decline of communities or chiefs in Kibi district but to be the change in meaning of burial mounds in society during this period.To confirm this, the investigators excavated Tenguyama tumulus in Mabi town to find a lot of articles useful for dating of this tomb, and to reveal that the change includes the transition of the type of burial chamber with the effects from Korean peninsular.As a result, the investigator concludes that the epoch of the Yuryakucho era should to be regarded as the long-term socio-cultural change rather than drastic political change in the view of archaeological research.