In the Ming period, the Manchus lived in dispersed communities in what is loosely called Manchuria (the northeast of modern-day China). In the more densely populated southern part of Manchuria, the Manchus lived in close contact with Mongols, Koreans, and Chinese (Map 21.1). They were not nomads but rather hunters, fishers, and farmers. Like the Mongols, they also were excellent horsemen and archers and had a strongly hierarchical social structure, with elites and slaves. Slaves, often Korean or Chinese, were generally acquired through capture. Manchu villages were generally small and often at odds with each other over resources. Interspersed among these Manchu settlements were groups of nomadic Mongols who lived in tents.

The Manchus credited their own rise to Nurhaci (1559–1626). Over several decades, he united the Manchus and expanded their territories. Like Chinggis Khan, who had reorganized the Mongol armies to reduce the importance of tribal affiliations, Nurhaci created a new social basis for his armies in units called banners. Each banner was made up of a set of military companies and included the families and slaves of the soldiers. Each company had a hereditary captain, often from Nurhaci’s own lineage. When new groups were defeated, their members were distributed among several banners to lessen their potential for subversion.

The Manchus entered China by invitation of the distinguished Ming general Wu Sangui, who was near the eastern end of the Great Wall when he heard that the rebels had captured Beijing. The Manchus proposed to Wu that they join forces and liberate Beijing. Wu opened the gates of the Great Wall to let the Manchus in, and within a couple of weeks they occupied Beijing. When the Manchus made clear that they intended to conquer the rest of the country and take the throne themselves, Wu and many other Chinese generals joined forces with them. Before long, China was again under alien rule.

Once securely in power, the Qing put in place policies and institutions that gave China a respite from war and disorder. Most of the political institutions of the Ming Dynasty were taken over relatively unchanged, including the examination system.

After peace was achieved, population growth took off. Between 1700 and 1800 the Chinese population seems to have nearly doubled, from about 150 million to over 300 million. Population growth during the eighteenth century has been attributed to many factors: global warming that extended the growing season, expanded use of New World crops, slowing of the spread of new diseases that had accompanied the sixteenth-century expansion of global traffic, and the efficiency of the Qing government in providing relief in times of famine.