Doi Shohei: Emergence of Standardized Tumuli (kofun) in the Third-century Northern Kantô in Eastern Japan

12/3 - 12/4/2014

Emergence of Standardized Tumuli (kofun) in the
Third-century Northern Kantô in Eastern Japan 弥生・古墳時代移行期の群馬県域における古墳出現過程
DOI Shohei土井翔平, Ph.D. Candidate in Archaeology, Meiji University

This paper explores the process behind the appearance of the highly standardized tumuli or kofun in the third-century northern Kantô region of eastern Japan. It has previously been a well-accepted hypothesis that keyhole-shaped tumuli appeared in eastern Japan in the middle third century under the cultural influence of the Tôkai region, Pacific coastal region of the central Honshu, and that people’s life style and mortuary practices came to be unified in the fifth century. The problem of this hypothesis is that it supposes that all the cultural influences from the west were uniform across the entire eastern Japan, which was not necessarily the case. In terms of methodology, it is also problematic that data are skewed toward large keyhole-shaped tumuli. The latter problem is particularly apparent in Gumma Prefecture, northern Kantô. While the overwhelming majority of tumuli of the mid-third century are small ones, from ten to 30 meters in length, discussion of the appearance of tumuli is based on keyhole-shaped tumuli of more than 100 meters in length.

In order to cope with these problems, the author has looked at all the tumuli of the mid-third century in Gumma Prefecture, paying particular attention to the mound form, mound size, pottery offered to the dead, and goods deposited with the dead. As a result of the author’s analyses, it has become clear that in the late third and early fourth centuries, there were two distinctive cultural flows from the Tôkai region. These two were spatially distributed on the northern side and southern side of the Tone River. As to mortuary rituals, the author has found that pots offered at tumuli morphologically changed from ritualistic ones in the fourth century to more practical ones in the fifth century. By paying attention to regionally and locally various patterns and taking several types of material cultures into consideration, the author’s research broadens our understanding of a very complex process that underlay the appearance of standardized tumuli in eastern Japan.