The four coin-issuing tribes of the peripheral zone separated the southern core zone from the less developed areas of western and northern Britain and it was through their territories that raw materials and other commodities had to pass in the period of intensiﬁed trade that characterized the Late Iron Age. Thus they formed a buffer zone between the developed and underdeveloped parts of the island. Their socio-economic systems must, therefore, have evolved to provide the enabling mechanisms necessary for the through ﬂow of products. The emergence of a peripheral zone, along the Jurassic Ridge, is no accident since this broad geomorphological region, providing ease of communication along its length, effectively divides Britain into two parts, each with different resource potential, microclimate and degree of access to Continental trading networks. The communities occupying the ridge would thus become subjected to economic forces once cross-Channel trade intensiﬁed. This may have led to the emergence of large tribal entities by the coalescence of smaller ethnic groups and would, in any event, have necessitated the development of a coinage to facilitate exchange.