In some ways, the period from 220 to 580 can be compared with the period of the coincidentally synchronous breakdown of the Roman Empire: in both cases there was no great increase in population, although in China perhaps no over-all decrease in population as in the Roman Empire; decrease occurred, however, in the population of the great Chinese cities, especially of the capital; furthermore we witness, in both empires, a disorganization of the monetary system, i.e. in China the reversal to a predominance of natural economy after some 400 years of money economy. Yet, this period cannot be simply dismissed as a transition period, as was usually done by the older European works on China. The social order of the gentry, whose birth and development inside China we followed, had for the first time to defend itself against views and systems entirely opposed to it; for the Turkish and Mongol peoples who ruled northern China brought with them their traditions of a feudal nobility with privileges of birth and all that they implied. Thus this period, socially regarded, is especially that of the struggle between the Chinese gentry and the northern nobility, the gentry being excluded at first as a direct political factor in the northern and more important part of China. In the south the gentry continued in the old style with a constant struggle between cliques, the only difference being that the class assumed a sort of "colonial" character through the formation of gigantic estates and through association with the merchant class. To throw light on the scale of events, we need to have figures of population. There are no figures for the years around A.D. 220, and we must make do with those of 140; but in order to show the relative strength of the three states it is the ratio between the figures that matters. In 140 the regions which later belonged to Wei had roughly 29,000,000 inhabitants; those later belonging to Wu had 11,700,000; those which belonged later to Shu Han had a bare 7,500,000. (The figures take no account of the primitive native population, which was not yet included in the taxation lists.) The Hsiung-nu formed only a small part of the population, as there were only the nineteen tribes which had abandoned one of the parts, already reduced, of the Hsiung-nu empire. The whole Hsiung-nu empire may never have counted more than some 3,000,000. At the time when the population of what became the Wei territory totalled 29,000,000 the capital with its immediate environment had over a million inhabitants. The figure is exclusive of most of the officials and soldiers, as these were taxable in their homes and so were counted there. It is clear that this was a disproportionate concentration round the capital.