Part of the difficulty these rulers faced can be traced to the emergence of a hereditary aristocracy that entrenched itself in the higher reaches of officialdom. Much more than in the Han period, these families judged themselves and others on the basis of their ancestors, and would only marry with other families of equivalent pedigree. They even compiled lists, complete with genealogies, of the most eminent families. By securing near automatic access to higher government posts through the Nine Rank system, the aristocrats were assured of government salaries and exemptions from taxes and labour service. Many were also able to build up great landed estates worked by destitute refugees from the north who were settled as self-like dependants. At court, the aristocrats often set themselves at odds with the 'upstart' rulers, doing what they could to frustrate these emperors' efforts to appoint or promote whom they wished. But the aristocrats should not be looked on as foes of Chinese civilization. The men in these families saw themselves as embodying Chinese civilization, maintaining the high cultural accomplishments of Han dynasty and the tradition of scholar-official. The solidarity of these cultivated families provided a centre around which Chinese culture could adhere during a period when no state could serve that function.

Constructing a capital south of the Yangzi had a beneficial effect on economic development of the south. When Luoyang fell in 311, the south probably had only about 10 per cent of the registered population of the Jin (which did not include non-Chinese, indigenous people of the south who paid no taxes). To pay for an army and to support the imperial court and aristocracy in a style that matched their pretensions, the government had to expand the area of taxable agricultural land, whether through settling migrants or converting the local inhabitants into tax-payers. The south, which its temperate climate and ample supply of water, offered nearly unlimited possibilities for such development.