Archaeological Research on Yuryakucho Era (later 5th century)

该项目旨在分析由yakucho时代（后5世纪）的社会转型，这被认为是日本中部群岛形成古代国家的一个伟大时代。为了实现这一目标，研究人员检查了锁眼形土丘的分布和过渡，重点关注了被认为代表Kibi地区当地主要血统的一系列土丘。研究人员发现，在由屋町时代，许多地区出现了锁眼状墓室的主要世系，而中部地区则消失了冢山（Zozan）和冢山（Sakuzan）等雄伟的墓葬。这表明每个地方社区开始将他们的劳动力主要用于埋葬。调查人员宣称，这不能解释为Kibi地区的社区或酋长的衰落，而是这一时期墓地在社会意义上的变化。为了证实这一点，研究人员在马比镇的天古山墓群中挖掘了大量可以用来确定该墓室年代的物品，并揭示了这种变化包括受朝鲜半岛影响而发生的墓室类型的转变。因此，研究人员认为，从考古研究的角度来看，由yakucho时代应该被视为长期的社会文化变化，而不是剧烈的政治变化。

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.