The so-called "feudal lords" (zhuhou 諸侯) were the highest members of the nobility of the Zhou period 周 (11th cent.-221 BCE). During the foundation of the Zhou dynasty, King Wu 周武王 enfeoffed (feng 封) some of his relatives (tongxing zongzu 同姓宗族) as well as non-cognate meritorious generals and leaders (yixing gongchen 異姓功臣).
The title of nobility was endowed with a territory, the seats of which were called guo 國 (actually a word for a walled city), a word that from the Spring and Autumn period 春秋 (770-5th cent. BCE) on the territories of the fiefs. Another word for the territory was bang 邦. It became obsolete during the Han period 漢 (206 BCE-220 CE) as a taboo word, because Bang was the the personal name of the dynastic founder, Liu Bang 劉邦 (Han Gaozu 漢高祖, r. 206-195 BCE).
The number of fiefs during the early phase of the Western Zhou 西周 (11th cent.-770 BCE) was 71. Their number shrank in the Spring and Autumn period. Some lines of feudal lords of smaller fiefs died out, while other territories were swallowed up by larger states. The conflicts of the Warring States period 戰國 (5th cent.-221 BCE) reduced the number of fiefs to seven large states: Chu 楚, Han 韓, Qi 齊, Qin 秦, Wei 魏, Yan 燕, and Zhao 趙. Because Qin conquered the others and founded the Qin empire in 221, the others are known as the "six feudal states" (liu guo 六國).
The title conferred upon the early Western Zhou feudal lords was hou 侯, usually translated as "marquis". The word zhuhou meant in the Western Zhou period "the many marquesses" or "the many feudal lords". Hou was the highest title of nobility, while lower ones were conferred upon persons of lesser merit. These "earls" (bo 伯), "viscounts" (zi 子) and "barons" (nan 男) were granted hereditary fiefs, too.
The word gong 公, usually translated as "duke", was originally not a rank of a noble, but referred to a state office with a defined function at the royal court (see Three Dukes). Various written sources, including bronze vessel inscriptions, do not make a clear difference between gong, hou and bo. The Gongyangzhuan 公羊傳 commentary on the "Spring and Autumn Annals" Chunqiu 春秋 explains the use of bo instead of hou as an expression of critique. It seems that from some point of time, the "earls" and "marquesses" appropriated the title of duke.
The feudal lords had the obligation to bring the Zhou king tributes, to supply him with personnel for state offices, to participate in military expeditions, and to supervise labour activities like the construction of canals (see yaoyi 徭役). In return they possessed hereditary rights over their territory.
After the downfall of the Western Zhou and with the decreasing strength of the royal house, the feudal territories won independence, and one usually speaks of "feudal states" during the Spring and Autumn and the Warring States periods. These states were connected to each other by an intricate system of ritual and ceremonial relationships, and "diplomatic missions" forged ties or carried out intrigues. In the second half of the Warring States period, the stronger of the feudal lords adopted the title of king (wang 王), and thus created a multi-state world out of an ancient feudal system.
The use of such a "feudal system" can be attested already for the Shang dynasty 商 (17th-11th cent. BCE). After the disintegration of the Zhou kingdom, the term zhuhou continued to refer, as a generic term, to persons bearing a title of nobility. While the Han dynasty only used the title of hou (apart from wang for princes), the full range of the five titles of nobility (including gong) was applied again during late imperial times.