East Asia faced many internal and external challenges between 800 and 1400, and the ways societies responded to them shaped their subsequent histories. In China the first four centuries of this period saw economic growth, urbanization, the spread of printing, and the expansion of the educated class. In Korea and Japan aristocratic dominance and military rule were more typical of the era. All three areas, but especially China and Korea, faced an unprecedented challenge from the Mongols. The challenges of the period did not hinder creativity in the literary and visual arts.

Europe during these six centuries, the subject of the next chapter, also faced invasions from outside; in its case, the pagan Vikings were especially dreaded. Europe had a social structure more like that of Korea and Japan than of China, with less centralization and a more dominant place in society for military men. The centralized church in Europe, however, was unlike anything known in East Asian history. These centuries in Europe saw a major expansion of Christendom, both through conversion and migration. Although there were scares that the Mongols would penetrate deeper into Europe, the greatest challenge in Europe was the Black Death and the huge loss of life that it caused.