The well-field system was a land management system implemented during China's slave society. It is said to have been practiced as early as the Xia and Shang dynasties, but it truly developed and flourished during the Western Zhou Dynasty. The term "well-field" refers to dividing farmland into square plots of a certain area, each measuring one hundred paces in length and width, called a "field," with an area of one hundred mu, cultivated by one person, known as a "husband." Roads and irrigation channels crisscrossed between the fields, forming a shape resembling the Chinese character for "well," hence the name "well-field system." Lords forced commoners to collectively cultivate the well-fields, with nine square plots forming one "well." The surrounding eight plots were private fields, cultivated by eight households, with the harvest belonging to each household; the central plot was public land, jointly cultivated by the eight households, with all income going to the lord. This was the system of eight families forming a well and jointly tending the public field.
However, during the Western Zhou period, it was said that all land under heaven belonged to the king, so the ownership of the well-field system rested with the Zhou king, while the actual cultivators only had usage rights. The king granted land to feudal lords and ministers, making them land lords, and each year these lords had to pay tribute to the king. Moreover, these lords could only enjoy the well-fields, inheriting them according to the patriarchal system based on legitimate and collateral lines, without the right to sell or transfer them. The common people who labored in the well-fields were also considered appendages of the land, belonging to the lords, with no freedom to change occupations and unable to leave the land for their entire lives.
During the Western Zhou Dynasty, land lords at various levels designated thousands of fertile plots of land as "public fields" reserved for themselves. These fields, often located near rivers with hills behind and facing the sun, were easy to cultivate for good harvests and were large in area, thus also called "great fields." Lords appointed officials as field overseers, who prepared for the next year's spring plowing in winter by pairing laborers based on their physical condition and age into groups of two called an "ou," with two people working together known as "he ou," a method termed "ou geng." On the public fields of major lords, there were often thousands of such pairs of laborers. When spring arrived and the busy farming season began, at dawn each day, large numbers of commoners were driven to work on the lord's public fields. The appointed field overseers sat at the village entrance, counting the laborers present and monitoring their work, and at the end of the day's farming, the laborers had to be checked off by the overseers. Sometimes, the land lords themselves would personally go to the fields to supervise the commoners' labor. When autumn came for the harvest, the yield from the public fields piled up like mountains, all belonging solely to the lord. In the idle winter months, commoners performed various chores for the lord: men repaired houses and twisted ropes, while women spun yarn, wove silk, and made clothes, working from early morning until midnight. To prevent them from slacking off, the lords gathered them together to work in one place for easier supervision.
The lords distributed the land in the suburbs around the cities to common laborers of their own clan. These people lived in the city—that is, the "state"—and were thus called "guoren" (city dwellers). The guoren did not have to pay taxes, but they were responsible for military levies and conscription; in peacetime, they annually contributed a small jar of rice and a bundle of hay to the state as military expenses, while in wartime, they had to take up arms and serve as soldiers, supplying their own necessary equipment. They could serve in the military and receive education, primarily in rituals and military training, and were also known as "wufu" (warriors) or "shi" (scholar-officials). These people were self-sufficient commoners in society, seemingly not exploited, but the era was rife with frequent wars—whenever conflict arose, they had to fight; if victorious, all spoils went to the rulers; if defeated, they risked capture and enslavement. After returning home from war, they often found their fields neglected, barren, or even overgrown, leaving them to endure hunger. Thus, the status of the guoren was highly unstable. The more distant and infertile lands, far from the cities, were allocated by the lords to commoners living in the wilds, who were accordingly called "yeren" (wild dwellers). The lordly class considered them foolish, despised them, and referred to them as "mang" (ignorant folk). These people had no rights and could only farm for the lords or perform miscellaneous labor; they had to first cultivate the lords' large fields and, only after receiving permission, could they work their own small plots of land.
During the mid-Western Zhou Dynasty, land cultivators began to occupy private fields, and land transactions emerged among the nobility, leading to the appearance of individual private land ownership, where nine households shared a well-field without public land. In the late Spring and Autumn period, the State of Lu implemented the "initial tax on private fields," which recognized the land ownership of private field owners, gradually dismantling the well-field system. With the use of iron tools and the promotion of ox-drawn plowing, a new form of exploitation emerged—feudal landlords exploiting peasants. During the Warring States period, Shang Yang carried out reforms in the State of Qin, with the main content being "abolishing the well-field system" and "allowing people to buy and sell land," affirming individual land ownership, leading to the complete collapse of the well-field system.
The Well-Field System was the economic foundation of the Zhou Dynasty, and upon it, the Zhou established a corresponding political system—the Enfeoffment System. At the beginning of the Western Zhou Dynasty, rulers began enfeoffing vassals, primarily granting lands to relatives of the same surname, meritorious officials of different surnames, and descendants of ancient emperors. For example, King Cheng's younger brother Shu Yu was enfeoffed in Jin, Jiang Ziya was enfeoffed in Qi, and Weizi Qi, a descendant of the Shang kings, was enfeoffed in Song.
Duke of Zhou, Ji Dan, assisted King Cheng of Zhou for seven years, stabilizing the Zhou dynasty's rule before returning power to the king. To further consolidate Zhou governance, the Duke of Zhou "established rituals and created music," implementing a system of laws and regulations that upheld the hierarchy between rulers and subjects, as well as senior and junior ranks. These systems affirmed the supreme and absolute dominance of the Zhou king while using blood ties as a bond, stipulating that the eldest son born to the primary wife held priority in inheriting the throne—simply put, succession was based on legitimacy and seniority. In ancient society, polygamy was practiced, meaning a man could have one primary wife along with multiple secondary wives. The so-called legitimate son was the child born to the primary wife, while sons born to secondary wives were considered illegitimate sons. The legitimate son belonged to the main lineage and was the only one qualified to inherit the throne, whereas illegitimate sons were part of a collateral lineage, at most receiving a small fief or becoming subjects of the legitimate son. If the primary wife had multiple sons, the eldest was chosen first; if the primary wife had no sons, the eldest among the sons of secondary wives was selected to inherit the throne—this was called the rule of seniority.
This system was known as the patriarchal clan system within the royal family and the enfeoffment system at the state level. The Zhou king used enfeoffment to appoint his other sons, who were considered lesser lineages, as regional lords in various territories. These lords could establish their own states within their granted lands, forming a relationship with the king that mirrored the dynamic between local and central authority, as well as between lesser and greater lineages. The lands granted through this process were called "vassal states," "feudal states," or "enfeoffed domains," and the rulers governing these states were referred to as "vassal kings," "sovereigns," or "state lords." The lords had control over all resources within their granted territories, including the people, land, and revenues. Within their own states, the lords also followed the principle of passing the title to the eldest son of the principal wife as the main lineage, while enfeoffing their other sons as ministers and officials. These ministers and officials, in turn, would pass their titles to their eldest sons of the principal wife as the main lineage and distribute their property among their other sons of lesser lineages.
Sons were enfeoffed as shi (lesser nobles). In this way, based on the patriarchal clan system and the enfeoffment system, a pyramid-shaped hierarchical structure of the Son of Heaven—feudal lords—high-ranking ministers—shi was formed within the aristocratic ruling class. Under this system, feudal lords were required to obey the commands of the Zhou Son of Heaven, pay tribute and present themselves at court to report their duties, and their armies had to follow the orders of the Zhou Son of Heaven to defend the Zhou royal house and join in military campaigns. Within their own fiefs, feudal lords could further enfeoff their lands, appointing their own relatives as high-ranking ministers, who could in turn grant land and people to the shi, who likewise bore obligations to pay tribute and provide military service to their superiors.
Through the enfeoffment system, the Zhou royal family's relatives, in-laws, and meritorious officials established a number of new states, consolidating rule and expanding territory. This system formed a hierarchical structure headed by the Son of Heaven, which became the basic framework of Zhou society. By enfeoffing vassal lords, the Zhou king effectively controlled the entire realm, integrating the establishment of local governments with the consolidation of his own rule, making state power more structured and affirming the supreme authority of the Son of Heaven. The enfeoffment system was widely implemented across all vassal states, creating a unified system that promoted their prosperity and development. However, these vassal states enjoyed considerable independence, and as their power grew, it inevitably challenged the royal authority. By the Spring and Autumn period, the Zhou royal house had declined, with "rites and military campaigns issuing from the vassal lords," leading major states to engage in constant wars of annexation over land, population, and dominance over other states, resulting in a situation of hegemonic struggle and the breakdown of the enfeoffment system.
After the Qin Dynasty unified the six kingdoms, it abolished the enfeoffment system and implemented the prefecture and county system nationwide, which continued thereafter, although the enfeoffment system still existed to a certain extent.