If, however, we suppose that Southern Britain was divided during the period of Roman rule into estates cultivated by dependent tenants and slaves, there is much that would lead us to believe that the Roman agricultural system was retained by the English conquerors; even though, in the present state of our knowledge, we cannot directly prove continuity. The first and most important consideration is this: the English manorial system was substantially, and, indeed, in most of its details, similar to that which prevailed during the Middle Ages in Northern France and Western Germany. But these Continental conditions--it has, I think, conclusively been proved--were the direct continuation of conditions that had prevailed under Roman rule.[28] The natural conclusion is that what is true of the Continent is true also of England. This conviction is confirmed by looking at two of the fundamental characteristics of the English manor. The distinction between land _in villenage_ and land _in demesne_--the latter cultivated by the tenants of the former, but yet kept in the lord’s hands--is to be found in the mediæval manor, and in the Roman villa.[29] It is not to be found either in the tribal system of Wales,--which we may look upon as indicating the condition to which the Celtic inhabitants of Britain might have arrived if left to themselves; nor in Tacitus’ account of the ancient Germans, which probably furnishes us in general outline with a picture of the social organisation which the English brought with them. Both in Wales and among the ancient Germans there were slaves working in their masters’ houses, or on their farms, and there were also servile tenants paying dues in kind; but in neither case was there an obligation on the part of a tenant to labour on any other land than his own holding.