Historically, Zhuge Liang was a rather generous man. Even those who opposed himself, Zhuge Liang rarely engaged in physical annihilation. For example, his political enemies Li Yan, Liao Li and others, Zhuge Liang also dismissed them from office, and did not do anything to them. But there was only one person, Zhuge Liang, not only to kill his people, but also to exterminate his people. This person not only had a personal grudge with Zhuge Liang, but also had a "public vendetta" with him, and this person was Liu Bei's former important minister, Meng Da.
Meng Da, a Fufeng man, was born into a family of eunuchs and scholars, and was very good to the Great Counselor Fa Zheng. In the last years of the Han Dynasty, Meng Da and Fa Zheng went into exile in Shu and became subordinates of the local warlord Liu Zhang. However, Meng Da and Fa Zheng believed that Liu Zhang was cowardly by nature and had no talent, so they plotted together with Zhang Song and planned Liu Bei's entry into Shu.
Subsequently, Liu Bei turned against Liu Zhang, and Meng Da and Fa Zheng immediately defected to Liu Bei and were reused by Liu Bei. After the Battle of Hanzhong, Liu Bei had Meng Da march east from Hanzhong and capture the three counties of Shangyong.
However, during the capture of the Eastern Three Counties, Meng Da killed Fang Ling Taishou Puqi. However, this action angered the second-in-command of Liu Bei's group, Zhuge Liang. This is because Ku Qi is the husband of Zhuge Liang's eldest sister, that is, his brother-in-law. Zhuge Liang has been exiled to Jingzhou since childhood, and he and his eldest sister are dependent on each other, although Meng Da may not have intended to kill Qu Qi, but I am afraid that it also brought great influence to Zhuge Liang. At that time, Zhuge Liang may have been out of public conscience and did not embarrass Meng Da.
After Meng Da occupied the Eastern Three Counties, he soon became a powerful faction under Liu Bei. The three eastern counties are bordered by the three kingdoms of Wei, Wu and Shu, and the geographical location is very dangerous. In order to restrain Meng Da, Liu Bei sent his adopted son Liu Feng to the Eastern Three Counties to form a two-headed system with Meng Da. Because of Liu Feng's rough style and repeated humiliation of Meng Da, the relationship between the two deteriorated sharply.
Subsequently, Guan Yu was raided by Lü Meng and besieged by Wei and Wu at the junction of Xiangyang and Fancheng. In order to get out of the predicament, Guan Yu sent someone to ask Liu and Meng for help. However, Liu Feng, Meng Da, and Guan Yu had a personal grudge, so they chose not to move, knowing that Liu and Meng were only a few tens of miles away from Guan Yu. After Guan Yu's defeat, Meng Da was afraid of being punished, so he secretly communicated with the State of Wei, and finally, with the help of the local clan Of shen, expelled Liu Feng and surrendered to the State of Wei with the four thousand families of Buqu and the three eastern counties.
Meng Da's betrayal completely angered Zhuge Liang. In Zhuge Liang's Longzhong alignment, spanning Jingzhou and Yizhou was his most basic strategic plan. Because Meng Da could not be saved by seeing death, he not only broke Guan Yu, but also lost Jingzhou to the State of Wu; at the same time, Meng Da surrendered to the State of Wei, leaving the State of Shu without its last foothold in Jingzhou. Since then, Zhuge Liang's "Longzhong Pair" has almost completely gone bankrupt. Whether out of public or selfish intentions, Zhuge Liang and Meng Da formed a vendetta against each other.
Therefore, Zhuge Liang made a rare move, he suggested to Liu Bei that he must kill Meng Da's family members who remained in Shudi. However, Liu Bei did not do this for various reasons, on the contrary, he treated Meng Da's wives kindly and did not blame them.
After Liu Bei's death, Zhuge Liang took over his scepter and monopolized the power of Shu Han. Before the Northern Expedition, Zhuge Liang miraculously threw an olive branch to Meng Da. He repeatedly wrote letters to Meng Da, hoping that he would return to the Shu kingdom. At that time, the Wei Wen Emperor Cao Pi, who valued Meng Da, had died, and he was in a state of panic after losing his patron. After receiving Zhuge Liang's letter, Meng Da was overjoyed and agreed.
Originally, Zhuge Liang could restore the Eastern Three Counties without a fight, and could use this area to pose a threat to Cao Wei's Xiangyang. However, Zhuge Liang made an unexpected choice: even if he didn't want the Eastern Three Counties, he would kill Meng Da! At that time, Meng Da sent envoys to give Zhuge Liang a piece of jade and a hat. The so-called Yu Jue indicates that the plot has been decided; and the Lun hat is exactly the hat that Zhuge Liang often wears. Meng Da's rebellion against Wei and his return to Shu's heart were clearly revealed.
After receiving Meng Da's gift, Zhuge Liang, instead of sending troops to receive Meng Da, instead publicized the news of Meng Da's rebellion against Wei. After that, the State of Wei, who heard the news, immediately sent Sima Yi to lead an army to quell the rebellion. After that, Sima Yi marched 1200 miles in eight days and hit Shangyong City like a fly. In the face of Meng Da's repeated requests for help, Zhuge Liang did not move and sat still and watched his death. In the end, Meng Da was defeated and killed, and all his family members in Shangyong were killed, and Zhuge Liang's purpose of killing people with a knife was achieved.
In the author's opinion, Zhuge Liang naturally has its reasonableness in getting rid of Meng Da, after all, he has a vendetta against Zhuge Liang, and his behavior is repetitive and difficult to trust. However, Meng Da died, and the Shu state lost the opportunity to regain the three eastern counties. Originally, the Shu army could go down the river from Hanzhong and join forces with the State of Wu to attack Xiangyang, which was occupied by the State of Wei. If Xiangyang is breached, Zhuge Liang's concept of "Longzhong Pair" from Jing and Yi to Wei can be re-realized. At that time, the State of Wu sent troops from Jiangling or Huainan to cooperate, and the State of Wei would fall into the dilemma of being attacked from the belly and back. Even if the great cause of "reviving the Han Dynasty" could not be successful, at least there would be no embarrassing situation in which the Shu Han Dynasty had been carried out more than ten times before and after the Northern Expedition from Hanzhong and returned without success. Perhaps, this is also a mistake of Zhuge Liang!