Western Zhou Dynasty

The Western Zhou period (1046–771 BC) was the first half of the Zhou dynasty of ancient China. It began when King Wu of Zhou overthrew the Shang dynasty at the Battle of Muye. The dynasty was successful for about seventy-five years and then slowly lost power. The former Shang lands were divided into hereditary fiefs which became increasingly independent of the king. In 771, the Zhou were driven out of the Wei River valley; afterwards real power was in the hands of the king's nominal vassals.

Few records survive from this early period and accounts from the Western Zhou period cover little beyond a list of kings with uncertain dates. King Wu died two or three years after the conquest. Because his son, King Cheng of Zhou was young, his brother, the Duke of Zhou assisted the young and inexperienced king as regent. Wu's other brothers (Shu Du of Cai, Guan Shu, and Huo Shu), concerned about the Duke of Zhou's growing power, formed an alliance with other regional rulers and Shang remnants in a rebellion. The Duke of Zhou stamped out this rebellion and conquered more territory to bring other people under Zhou rule.

The Duke formulated the Mandate of Heaven doctrine to counter Shang claims to a divine right of rule and founded Luoyang as an eastern capital. With a feudal fengjian system, royal relatives and generals were given fiefs in the east, including Luoyang, Jin, Ying, Lu, Qi and Yan. While this was designed to maintain Zhou authority as it expanded its rule over a larger amount of territory, many of these became major states when the dynasty weakened. When the Duke of Zhou stepped down as regent, the remainder of Cheng's reign (1042–1021 BC) and that of his son King Kang of Zhou (1021–996 BC) seem to have been peaceful and prosperous.

The fourth king, King Zhao of Zhou (996–977 BC) led an army south against Chu and was killed along with a large part of the Zhou army. The fifth king, King Mu of Zhou (977–922 BC) is remembered for his legendary visit to the Queen Mother of the West. Territory was lost to the Xu Rong in the southeast. The kingdom seems to have weakened during Mu's long reign, possibly because the familial relationship between Zhou Kings and regional rulers thinned over generations so that fiefs that were originally held by royal brothers were now held by third and fourth cousins; peripheral territories also developed local power and prestige on par with that of the Zhou royal family.

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