The Romance of the Three Kingdoms is mainly about the chaotic world and the struggle for glory, and in the early stages of the book, it constructs a fierce battle situation in which wolves smoke and soldiers are fighting each other, that is, in the sixth year of Zhongping (189), the Dong Zhuo crusade took place in the Central Plains and Guanzhong regions, with the Kwantung Combined Army and the Liangzhou Army as the main participants. The Eighteenth Route Princes led a crusade against Dong Zhuo's army of 50,000. Sounds a bit exaggerated, eighteen ways to one way, isn't that killing chickens with a cattle knife? In fact, there are at least four reasons for this.
The reason for the crusade against Dong Zhuo

The first is that Dong Zhuo deceives people too much, is absurd, and causes public anger. Since Emperor Dong Zhuo killed Emperor Dong Zhuo, he raped the palace women every night, and even when the people gathered to organize activities, he killed thousands of villagers for no reason, hung their heads above the city tower, and distributed the looted women's belongings to the evil soldiers who followed him. Since Dong Zhuo came to power, the people have not had a good life, the people are afraid day and night, and the society is extremely unstable. The attack of the Eighteenth Route Princes was entirely in accordance with the will of the people, and it was Dong Zhuo's own bad consequences.
The second is the ambition of the princes, the banner of "maintaining orthodoxy and conforming to the heavenly path" is the best cover for the princes to expand their territory and increase their strength, so these eighteen princes do not want to fall behind. Yuan Shao learned in Bohai that Dong Zhuo had gained power, so he wrote to Wang Yun. It is said that Dong Zhuo not only sought power and usurped the throne, but also became the head of a country with an unjust name, but also burned and robbed without evil, and the people suffered unspeakable. As loyal subjects to the country, in order to preserve the inheritance handed down from our ancestors, we might as well unite to uphold justice. Therefore, the eighteen princes of the Eighteen Roads immediately agreed, and they all wanted to create some achievements in the chaotic world, and began the method of unity.
The third is the reason for strength. Although the Kwantung Coalition Army had eighteen forces, it only had more than 100,000 people, and Dong Zhuo alone had 50,000 horses. Before forcing the palace, Dong Zhuo had previously been made a general by Emperor Xian, the Marquis of Aoxiang, and the Assassin of Xiliang, and had formed a party in the imperial court for personal gain, promoted new people, organized his own strength, and he also commanded a large army of 200,000 in Xizhou, with strong strength, if the princes did not unite, they could not win Dong Zhuo alone.
The fourth is that the princes are not willing to give their all, and can only pay part of their troops. At first, the coalition forces were afraid of Dong Zhuo's strong forces and were reluctant to go first, so Cao Cao led his troops to the west and stationed in Chenggao, which opened the prelude to the crusade. By the time of the war, there were two hearts between Han Fu and Yuan Shao, and Han Fu deliberately reduced grain delivery; Liu Dai and Qiao Mao had always been at odds, and Liu Dai killed Qiao Mao. Dong Zhuo's crusade was nominally to unite to resist the enemy, but in fact, the eighteen princes were jealous of each other and wanted to be alone, and they were unwilling to be "head birds" and left their backs to others.
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Romance of the Three Kingdoms