"Going through five customs and beheading six generals": Guan Yu got rid of Cao Cao and defected to Liu Bei after going through five customs and beheading six generals. Later, the metaphor was full of praise for the great courage or determination to overcome many difficulties.

Five passes: Dongling Pass, Luoyang Pass, Sishui Pass, Xingyang Pass and Huazhou Yellow River Ferry.

Six generals: Luoyang satrap Han Fu, tooth general Meng Tan; Kong Xiu, Dongling Pass; Si Shuiguan Bian Xi; Wang Zhi in Xingyang and Chyi Chin in Huazhou.

Extended information Guan Yu, a famous soldier in the late Eastern Han Dynasty. When Liu Bei started his army, Guan Yu followed Liu Bei and was loyal and trusted by Liu Bei. Liu Bei, Zhuge Liang and others entered Shu, and Guan Yu guarded Jingzhou. After Liu Bei captured Hanzhong, Guan Yu took advantage of the situation to explore Wei. He besieged Xiangfan, escaped from the Forbidden City, beheaded Pound, threatened China, and the Central Plains shook, but Wu Dong attacked Jingzhou, and Guan Yu was defeated and killed.

After Guan Yu's death, he was gradually deified by people and was honored as "Guan Gong". There have been many awards and titles in all previous dynasties. In Qing Dynasty, it was regarded as "loyal to SHEN WOO, brave to show great sage" and "warrior sage", just like Confucius "Wen Sheng". The Romance of the Three Kingdoms honored him as the leader of the "Five Tiger Generals" in Shu, and Mao Zonggang called him the "righteous person" of the "Three Wonders of Romance".

Story background: Liu Beijun was defeated by Cao Cao, and Liu, Guan and Zhang were separated. Guan Yu was surrounded by Cao. Cao Cao greatly appreciated Guan Yu's talent and bravery. Cao Cao wanted Guan Yu to surrender, so he sent Zhang Liao (Wen Yuan) to lobby Guan Yu. Guan Yu agreed to surrender to Cao Cao temporarily out of loyalty to his younger brother Liu Bei and friendship with Zhang Liao.

However, several requirements were put forward: first, surrender to Korea rather than to Cao; The second is to ensure the safety of brothers and sisters; Third, if there is news of Liu Bei, he should leave at once, and Cao can't stop him.

Cao Cao was so eager to love talents that he had to agree, hoping to influence Guan Yu to surrender sincerely through his own efforts. In the days when Guan Yu "surrendered" to Cao Cao, Guan Yu received extremely high treatment, was named Hou Ting of Hanshou, and was given the title of "Red Rabbit Horse". Guan Yu is not unrequited love. Beheading Yan Liang and punishing Wen Chou made great contributions.

Just as things went on like this, suddenly, Guan Yu got the news of Liu Bei and immediately resigned from Cao Cao, but Cao Cao avoided it. Finally, Guan Yu had to leave without saying goodbye. Because he didn't get Cao Cao's instructions, all the way was blocked, but Guan Yu passed the five customs under Cao Cao's jurisdiction by himself and beheaded six generals of Cao Cao.

References:

Baidu Encyclopedia-Go through Five Customs and Cut Six Generals