The Western Zhou was a period of Chinese history corresponding roughly to the first half of the Zhou dynasty. It began when King Wu of Zhou overthrew the Shang dynasty at the Battle of Muye and ended in 771 BC when Quanrong pastoralists sacked the Zhou capital at Haojing and killed King You of Zhou. The "Western" label for the period refers to the location of the Zhou royal capitals, which were clustered in the Wei River valley near present-day Xi'an.