Several hundred enclosed protohistorical settlements have been discovered in Japan since the 1950s. They date mainly from the Yayoi period (350 BC to 300 AD) and the early Kofun period (300 to 700 AD). These sites can be interpreted as the remains of rural settlements. In this volume the author develops a detailed analysis of these sites using his experience of the study of similar sites in south-western England and north-western France. Distribution maps drawn at a general, regional and local scale reveal the keys of territorial development during protohistory. The archaeological evidences found inside the enclosures allows various interpretations of the role of these communities in the society of Yayoi period. In situ architectural reconstitution of protohistorical building architecture suggests structural links with Japanese mediaeval classical architecture. The author also describes other protohistorical enclosed settlements in continental eastern Asia and this enlarges the general research. The workconcludes with a detailed comparison of protohistorical enclosed settlements in Japan and north-western France and south-western England.