Prof. Ken’ichi Sasaki, Meiji University, “Archaeological Excavation at a Seventh-century Keyhole Tomb in Southern Hitachi” 「 常陸南部における7世紀前方後円墳の発掘調査」
This paper reports major results of the archaeological excavation that I conducted at a seventh-century keyhole mounded tomb in March, 2017, in the region of southern Hitachi. This mounded tomb has been known among scholars for its burial chamber of painted red walls. My excavation resulted in the discovery of two moats enclosing the mounded tomb. While keyhole tombs enclosed by two or three moats were common in the fifth century in the Kawachi and Izumi regions where the central polity was presumably located at the time, it is extremely unusual to find such a moated tomb mound from the seventh century. In other regions of Japan, in the late sixth century after Buddhism was introduced to Japan, the construction of keyhole mounded tombs declined. In place of the tombs, Buddhist temples became symbols of authority. Indeed, the construction of the temple of Asukadera was completed in 596 in Yamato. This unusual seventh-century keyhole mounded tomb enclosed by two moats may be interpreted in two ways: information from the central polity did not reach Hitachi, on the eastern periphery, rapidly; or local elites in Hitach were so conservative that they were wedded to old customs.