Archaeology of Salt in Japan

Introduction and Definition

Seawater has been the primary resource for producing salt in Japan because of the absence of rock salt, salt lake, and salty soil (Kondō 1975). The only exception is salt springs which usually contain much less salt than seawater. Few places are known to have produced salt by salt springs in the early modern to the modern period. Salt production in Japan has developed along the seacoast which had suitable climatic conditions for producing salt. The first evidence of salt production was salt-producing pottery which had appeared in the Late Jōmon (ca. 1,500BC) (Kondō 1962; Kawashima 2012b, 2015). Salt pottery was distributed along the Pacific coast in eastern Japan (Fig. 1). While the tradition of the Jōmon salt production existed till the Middle Yayoi period in the northern region, in the same period, salt pottery appeared in the Inland Sea area which has been the most crucial salt production area in Japan till the contemporary period (Fig. 2). Salinity of...