On the Radiocarbon Dating of the Yayoi Period

Abstract

Using the results of high-precision AMS dating, researchers at the National Museum of Japanese History have recently proposed that the Yayoi period began at 1000 B.C., that the Early Yayoi phase started at 800 B.C., and that the transition from the Early to Middle Yayoi occurred around 400 B.C. Based on these dates, the Museum has further suggested a fundamental reevaluation of the historical context of the Yayoi period, linking the beginning of the Yayoi with the fall of the Shang dynasty and the establishment of the Western Zhou, and the start of the Early Yayoi with the fall of the Western Zhou and the commencement of the Spring and Autumn period. If the date of 400 B.C. is correct for the start of the Middle Yayoi, then that would also place it in the Warring States period and would thus contradict existing explanations based on the influx of bronze artifacts into the Korean Peninsula.
In this paper, the author compared the fragment of an iron tool found from an Initial Yayoi pit-house at Magarita with iron tools from Shang, Zhou, Spring and Autumn, and Warring States China. In the Shang and Zhou, iron was a novel substance used like beads in ritual contexts and it is most appropriate to see the Magarita tool fragment as belonging to the Warring States period, meaning that the Initial Yayoi cannot be dated as early as the 9th or 10th centuries B.C. The author then takes up the question of Liaoning-type bronze daggers using the chisels from the beginning of the Early Yayoi that were found at the Imagawa site. These chisels were made using the stems of stemmed bronze arrowheads and Liaoning-type daggers. The author argues that even if we place the first Liaoning-type daggers at the end of the Western Zhou or the start of the Spring and Autumn period and suggest that they only indirectly influenced the daggers of the Korean Peninsula which then reached Japan, it is not possible to conclude that the Early Yayoi began around 800 B.C. Finally, with respect to the transition between the Early and Middle Yayoi being placed around 400 B.C., the author notes the contradiction with existing theories regarding the diffusion of bronze artifacts and compares the dates of narrow-bladed bronze halberds from Korea and north Kyushu with those from Tomb 30 of the Yan Lower Capital of Xinzhuangtou.
Although not directly connected with the radiocarbon dates discussed here, the author also states his misgivings about using coins as a chronological basis.
From the above analyses, the author concludes that the chronology of the Yayoi period that he has built in his previous research is not seriously mistaken.