Abstract
In this article, I deal with the historical development of the Japanese language by applying a multi-disciplinary approach that uses data from a variety of fields. My research indicates that the home-land of the Japonic language family may have been in the lower Yangtze River Valley, from where its speakers moved to the Korean Peninsula and eventually to Japan during the Yayoi period. This spread is associated with the dispersal of wet rice agriculture from the area south of the Yangtze River via the northeastern Asian mainland, where it was in contact with cultures cultivating millet. Old Japanese mythology and genealogical data suggests that the earliest known ethnic group that spoke Japonic may have been the Hayato people of southern Kyūshū.1