Fēngjiàn (Chinese: 封建; lit. 'enfeoffment and establishment') was a political ideology and governance system in ancient China, whose social structure formed a decentralized system of confederation-like government based on the ruling class consisting of the Son of Heaven (king) and nobles, and the lower class consisting of commoners categorized into four occupations (or "four categories of the people", namely gentries, peasants, laborers and merchants). The system dated back at least to the Shang dynasty, but was formally coined during the Western Zhou dynasty when the Zhou kings enfeoffed their clan relatives and fellow warriors as vassals. Through the fengjian system, the king would allocate an area of land to a noble, establishing him as the de facto ruler of that region and allowing his title and fief to be legitimately inherited by his descendants. This created large numbers of local domains, which became autonomous states.
The rulers of these vassal states, known as zhūhóu (Chinese: 諸侯; lit. 'various marquess'), had a political obligation to pay homage to the king, but as the central authority started to decline during the Eastern Zhou dynasty, they eventually grew rebellious and developed into their own kingdoms, reducing the Zhou dynasty to merely an empty name. As a result, Chinese history from the Zhou dynasty (1046 BC–256 BC) to the beginning of the Qin dynasty has been termed a feudal period by many Chinese historians, due to the custom of enfeoffment of land similar to that in Medieval Europe. But scholars have suggested that fengjian otherwise lacks some of the fundamental aspects of feudalism. This system is often conflated with Confucianism but also with Legalism.
Each fengjian state was autonomous and had its own tax and legal systems along with its own unique currency and even writing style. The nobles were required to pay regular homage to the king and to provide him with soldiers in a time of war. This structure played an important part in the political structure of the Western Zhou which was expanding its territories in the east. In due course this resulted in the increasing power of the noble lords, whose strength eventually exceeded that of the Zhou kings, leading to dwindling central authority. The vassal states started to completely ignore the Zhou court and fight with each other for land, wealth and influence, which eventually disintegrated the authority of the Eastern Zhou into the chaos and violence of the Warring States period, where the great lords ended up proclaiming themselves as kings.
During the pre-Qin period, fengjian represented the Zhou dynasty's political system, and various thinkers, such as Confucius, looked to this system as a concrete ideal of political organization. In particular, according to Confucius, during the Spring and Autumn period the traditional system of rituals and music had become empty and hence his goal was to return to or bring back the early Zhou dynasty political system. With the establishment of the Qin dynasty in 220 BCE, the First Emperor unified the country and abolished the fengjian system, consolidating a new system of administrative divisions called the junxian system (郡縣制, "commandery-county system") or prefectural system, with the establishment of thirty-six prefectures and a rotational system for appointing local officials. There are many differences between the two systems, but one is particularly worth mentioning: the prefectural system gave more power to the central government, since it congealed power at the political center or the top of the empire's political hierarchy. From the Qin dynasty onward, Chinese literati would find a tension between the Confucian ideal of fengjian and the reality of the centralized imperial system.
After the establishment of the Han dynasty (206 BCE to 207 CE), Confucianism became the reigning imperial ideology and scholars and court officials alike again began to look to the Zhou dynasty fengjian system as an ideal. These scholars advocated incorporating elements of the fengjian system into the junxian system. The Han dynasty emperors ultimately chose to parcel out land to their relatives, thus combining the junxian and fengjian systems.