In 203 BC, during the Chu-Han Contention, Han Xin had subdued the entire state of Qi and sent a messenger to King Liu Bang requesting to be made acting King of Qi. At that very moment, Chu forces were tightly besieging the Han king at Xingyang. Upon reading Han Xin's letter, Liu Bang flew into a rage. Zhang Liang and Chen Ping secretly stepped on the king's foot and whispered in his ear, "Our Han army is in a difficult position right now. It would be better to formally appoint Han Xin as king to secure Qi, or else he might rebel." Liu Bang came to his senses, indeed made Han Xin the King of Qi, and mobilized his troops to attack Chu.
A man named Kuai Tong tried to persuade Han Xin to abandon Liu Bang, the Han king, and side with Xiang Yu instead. Han Xin replied, "When you ride in someone's carriage, you share their troubles; when you wear their clothes, you bear their worries; when you eat their food, you die for their cause. I cannot betray the Han king." Seeing his advice rejected, Kuai Tong feigned madness and became a shaman.
Later, Han Xin gradually realized that the Han emperor feared his talents, and he grew increasingly gloomy. Han Xin had a close friend, Chen Xi, the governor of Julu Commandery, and he urged Chen Xi to rebel against the Han emperor, promising to act as an inside man in the capital. In the tenth year of the Han reign, Chen Xi indeed rebelled, and the emperor personally led the army to suppress him. Han Xin, claiming illness, did not follow and secretly prepared to support the rebellion. However, unexpectedly, a retainer of Han Xin reported his plot to Empress Lu. Empress Lu wanted to summon Han Xin but feared he would not comply, so she falsely announced that Chen Xi had been captured and executed, and ordered all nobles and officials to come to congratulate her. Prime Minister Xiao He tricked Han Xin, saying, "Even if you are ill, you should force yourself to attend the celebration." Han Xin thus entered the palace. Empress Lu ordered warriors to bind Han Xin and executed him in the bell chamber of the Changle Palace. As he was dying, Han Xin said, "I regret not heeding Kuai Tong's advice; now I am deceived by a woman and a boy."
After returning from suppressing Chen Xi's rebellion, Emperor Gaozu of Han entered the capital to find Han Xin already dead. Delighted, he asked what Han Xin had said before dying. Empress Lu replied that Han Xin regretted not heeding Kuai Tong's advice. The emperor immediately ordered Kuai Tong's arrest. When Kuai Tong was brought before him, the emperor angrily declared, "Boil him alive!" Kuai Tong protested, "Boiling me is unjust. When the Qin dynasty lost the throne, all under heaven raced for it like deer in the field. Countless heroes wielded their blades to achieve what Your Majesty has done—they simply lacked the strength. Could you boil them all?" The emperor relented, saying, "Release him," and pardoned Kuai Tong's crime.
"The deer in 'chasing the deer on the Central Plains' is a homophone for 'emolument,' symbolizing the imperial throne and extending to political power. Later, people used 'chasing the deer on the Central Plains' to describe civil wars and heroes contending for the realm."
Source: *Records of the Grand Historian*, "Biography of the Marquis of Huaiyin"
Meaning of the Idiom: Later, the Chinese idiom "中原逐鹿" came to describe civil wars and heroes contending for the realm.