In terms of character, Meng Da in the Three Kingdoms period can be compared with Lü Bu. After all, Lü Bu was a family slave with three surnames, and Meng Da first betrayed Liu Zhang, then betrayed Liu Bei, and finally betrayed Cao Rui, meng Da can be regarded as a replica of the three surname family slaves.
Through this betrayal again and again, Meng Da's official position was getting higher and higher, and the power in his hands was also getting bigger and bigger. But in the final analysis, he is opportunistic, betrayed more often, and there will always be a day of self-destruction. For example, in 228 AD, when Meng Da was once again preparing for betrayal, he ended up with a defeat and was killed.
A big reason why Meng Da betrayed Liu Zhang was that he could not get Liu Zhang's reuse for a long time. Coupled with the fact that Liu Zhang did not have the enterprising spirit, this made Meng Da feel that there was no future in continuing to follow Liu Zhang, so he chose to betray Liu Zhang.
After joining Liu Bei's camp, although Meng Da was further promoted, it did not make Meng Da very satisfied. Coupled with the fact that a lot of things happened after Meng Da took the three counties of Shangyong, this led Meng Da to choose betrayal again.
The reason for this is that Meng Da betrayed Liu Bei for several reasons.
Soon after Liu Bei entered Shu, Meng Da, together with Fa zheng, deceived Liu Zhang's 4,000 troops, and Shunshi fell to Liu Bei's camp. It was only a little embarrassing that Fa Zheng was left by Liu Bei's side, while Meng Da was sent to Jiangling. From a certain point of view, this has quite the meaning of distributing frontiers, and in terms of treatment after surrender, it is certainly inferior to the Fazheng.
It should be known that Jiangling is under the jurisdiction of Guan Yu, that is to say, after Meng reaches Jiangling, he still has to accept Guan Yu's orders. In other words, he had to be monitored by Guan Yu.
After Liu Bei captured Xichuan, Meng Da was promoted to Yidu Taishou. When Liu Bei ascended the throne of Hanzhong, Meng Da was still Yidu Taishou. Compared with Liu Zhang's old department, which later surrendered to Liu Bei, there were many people whose official positions and status were above Meng Da, which made Meng Da seriously unhappy.
Like Liu Ba as Shangshu, Xu Jing as Taifu, Wu Yi as an escort, and Liu Bei's brother-in-law. Another example is That Huang Quan served as the governor of Yizhou Mu, and Li Yan served as the general of the Auxiliary Han Dynasty and the governor of Jiangzhou.
These people all surrendered to Liu Bei after Meng Da, and they were all passive and had to surrender. But what they didn't expect was that their official position and status were above Meng Da, and no matter who put this kind of thing on, it was unacceptable.
After Liu Bei took Hanzhong, he ordered Meng Da to capture the three counties of Shangyong. However, after Meng Da took Fangling Commandery, Liu Bei was worried that Meng Da was powerful, so he sent Liu Feng to the Shangyong front and let Liu Feng seize Meng Da's command.
What is even more excessive is that after the three counties of Shangyong were incorporated into Liu Bei's territory, Shen Tan, who surrendered, was given the title of General of Zhengbei and led Shangyong Taishou, and Shen Yi, who surrendered, was also named General jianxin and Taishou of Xicheng, and even Liu Feng, who came to pick peaches, was also given the title of deputy general.
What about Meng Da? There was nothing, Ming Ming made a great contribution to the capture of the three counties of Shangyong, and as a result, not only was there no reward, but even the command of his own army was robbed by Liu Feng, and he also became Liu Feng's deputy. Who wouldn't be angry about this kind of thing?
Liu Bei did not trust Meng Da and did not reuse Meng Da. After Meng Da made some achievements, most of the credit was robbed by Liu Feng. Therefore, it must be admitted that Liu Bei is really too much in this matter.
Liu Feng was a reckless man, although he was a fierce general, but it was easy to be arrogant and did not know the depth. As Liu Bei's righteous son, coupled with the fact that he was the commander sent by Liu Bei to the Three Counties of Shangyong, this made Liu Feng arrogant, so that he did not pay attention to Meng Da.
The first thing Liu Feng did after arriving in Shangyong was to absorb Meng Da's army and become the highest speaker of the three counties of Shangyong. In the Zizhi Tongjian, it is recorded:
The Shu general Meng Datun Shangyong (孟達屯上庸), who was in cavalier with the deputy general Liu Feng (劉封封), was enfeoffed with Lingzhi.
From this, it can be seen that Liu Feng and Meng Da did not have any contradictions.
There is also a sentence in the Romance of the Three Kingdoms:
He also sealed the discord with Da, and sealed the conquest of Da's advocacy.
Advocacy is a military band, a symbol of power and status. As a result, it was obviously Meng Da's military band, but it was forcibly snatched away by Liu Feng, which was undoubtedly punching Meng Da's face.
They have all been bullied to such an extent, and Meng Da's rebellion is really understandable.
In June 219, Meng Da and Liu Feng took the three counties of Shangyong. By August, Guan Yu had launched the Battle of Xiangfan, and Guan Yu had asked Meng Da and Liu Feng to send troops to participate in the Battle of Xiangfan.
However, Liu Feng and Meng Da believed that they had just taken the three counties of Shangyong and that the internal situation was still unstable, so they refused Guan Yu's request. Until Guan Yu was defeated and maicheng, and the soldiers were defeated and killed, Liu Feng and Meng Da were stationary and watched Guan Yu lose. There is no doubt that this must have caused Liu Bei's fierce anger.
Liu Bei, who was angry, directly gave Liu Feng death. It can be said that if Meng Da had not defected to Cao Wei at that time, perhaps he would have been executed.
Meng Da, who had an extremely sensitive sense of smell, was worried about this situation, so for the sake of his own life, he chose to surrender to Cao Wei.
The three counties of Shangyong are Fangling, Shangyong and Xicheng. When Meng Da captured Fangling County, he didn't know whether it was intentional or unintentional, anyway, Qu Qi, who was the Taishou of Fangling at the time, died in this war.
This Pu Qi was not only an excellent son of the Jingzhou Ku family, but he was also Zhuge Liang's brother-in-law, because one of Zhuge Liang's sisters was married to Chu Qi.
The Romance of the Three Kingdoms records this:
In the twenty-fourth year of Jian'an, Fengda returned from Zi to the north to attack Fangling, and Fangling Taishou Puqi was killed by Dabing.
In any case, the death of Zhuge Liang's brother-in-law, this account must be counted on Meng Da's head. This incident can be understood as Meng Da's provocation to Zhuge Liang.
Not only that, Ku Qi's influence in Jingzhou was very large, and in Liu Bei's camp, many figures of the Jingzhou Sect could more or less relate to Qu Qi. And Meng Da's move undoubtedly offended the entire Jingzhou faction.
In this situation, which offended Zhuge Liang, and even the entire Jingzhou faction, it was almost impossible to get promoted again and get rich. And this is unacceptable to Meng Da, because Meng Da has great ambitions, he wants to have more power, higher status. Since these ambitions could no longer be realized in the Shu Han camp, it was better to choose to surrender to Cao Wei and go to a better future.
All in all, there are two main reasons why Meng Da betrayed Liu Bei. The first is Liu Bei's distrust, and the other is that Meng Da feels that there is no future in continuing to follow Liu Bei. Speaking of which, Meng Da is an overly interest-oriented speculator, as long as someone can offer a very high price tag, then he will choose who to defect to.
For such a person, profit is the most important, and as for loyalty, it is a joke. In contrast, Lü Bu is also such a person, but Meng Da's situation is better, at least Meng Da has not been scolded as a "three-surnamed family slave".