By the 12th century BC, Shang influence extended west to the Wei River valley, a region that was occupied by clans known as the Zhou. King Wen of Zhou, the ruler of the Zhou, who was a Shang vassal, was given the title "Count of the West" by the King Di Xin of Shang. Di Xin used King Wen to guard his rear while he was involved in a south-eastern campaign. Eventually Di Xin, fearing King Wen's growing power, imprisoned him. Although Wen was later released, the tension between Shang and Zhou grew. Wen prepared his army, and conquered a few smaller states which were loyal to Shang, slowly weakening Shang's allies. However, King Wen died in 1050 BC before Zhou's actual offensive against Shang. Di Xin paid very little attention to these, as he viewed himself as the rightful ruler of China, a position appointed by the heavens, or perhaps because he was becoming engrossed with his personal life with his beautiful consort Daji, to the exclusion of all else. King Wen's son King Wu of Zhou led the Zhou in a revolt a few years later. The reason for this delay was because King Wu believed that the "heavenly order" to conquer Shang had not been given, as well as the advice of Jiang Ziya to wait for the right opportunity. Chinese civilians greatly supported King Wu's rebellion. In legend, Di Xin, initially, had been a good ruler. But after he married Daji, he became a ruthless ruler. Many called for the end of the Shang dynasty.
Battle
With Jiang Ziya as the strategist, King Wu of Zhou led an army of about 50,000. Di Xin's army was at war in the east, but he still had about 530,000 men to defend the capital city of Yin. But to further secure his victory, he gave weapons to about 170,000 slaves to protect the capital. These slaves did not want to fight for the corrupt Shang dynasty, and defected to the Zhou army instead. This event greatly lowered the morale of the Shang troops. When engaged, many Shang soldiers did not fight and held their spears upside down, as a sign that they no longer wanted to fight for the corrupt Shang. Some Shang soldiers joined the Zhou outright. Still, many loyal Shang troops fought on, and a very bloody battle followed, which is described in the Shijing, as translated by James Legge: The Zhou troops were much better trained, and their morale was high. In one of the chariot charges, King Wu broke through the Shang's defense line. Di Xin was forced to flee to his palace, and the remaining Shang troops fell into further chaos. The Zhou were victorious and showed little mercy to the defeated Shang, shedding enough blood "to float a log".
Aftermath
After the battle Di Xin adorned himself with many valuable jewels then lit a fire and burned himself to death in his palace on the Deer Terrace Pavilion. King Wu killed Daji after he found her with the order to execute her given by Jiang Ziya. Shang officials were released without charge with some later working as Zhou officials. The imperial grain store was opened immediately after the battle to feed the starving population. The battle marked the end of the Shang dynasty and the beginning of the Zhou dynasty.
