Commandery (China)

The commandery (Chinese: , p jùn, w chün), also translated as prefecture, was a historical administrative division of China from the Zhou dynasty (c. 7th century BCE) until the early Tang (c. 7th century CE).

During the later Zhou's Spring and Autumn period from the 8th to 5th centuries BCE, the larger and more powerful of the Zhou's vassal states—including Qin, Jin and Wei—began annexing their smaller rivals. These new lands were not part of their original fiefs and were instead organized into counties (xiàn). Eventually, commanderies were developed as marchlands between the major realms. Despite having smaller populations and ranking lower on the official hierarchies, the commanderies were larger and boasted greater military strength than the counties.

As each state's territory gradually took shape in the 5th- to 3rd-century BCE Warring States period, the commanderies at the borders flourished. This gave rise to a two-tier administrative system with counties subordinate to commanderies. Each of the states' territories was by now comparatively larger, hence there was no need for the military might of a commandery in the inner regions where counties were established. The border commanderies' military and strategic significance became more important than those of counties.

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