In just seven years, Zhuge Liang, the chancellor of the Shu Han Dynasty, had made such a northern expedition, and although he had made some gains, he had not achieved the goal of "reviving the Han Dynasty", and even Zhuge Liang himself fell ill and died in Wuzhangyuan.
So why did Zhuge Liang insist on the Northern Expedition? The first reason is the revival of the Han Room, which was also expressed in Zhuge Liang's "Table of Teachers", after all, this is also Liu Bei's last wish. The second reason is to divert domestic contradictions. After Liu Bei's death, it actually meant that the veteran generals who had followed him for many years were also gone, and the problems in the Shu Han Dynasty were not small, and there were frequent rebellions in the south, which were all problems, so the Northern Expedition could divert domestic contradictions and be consistent with the outside world. The third reason was that Cao Wei could not be made bigger.
The first reason is the revival of the Han Room
Liu Bei was a relative of the Han Dynasty, and although by the time of his generation, he was not as good as ordinary people, but after all, he was the King of Zhongshan Jing, and it was extremely painful to see the Han Dynasty become like this. And he also relied on the slogan of reviving the Han Dynasty to win over many people, although the Shu Han was established, but the wish of the Central Plains in The North was not realized.
And Liu Bei is even more grateful to Zhuge Liang, not to mention that Liu Bei was still orphaned before his death, then Zhuge Liang had this mission to fulfill the last wish of the former emperor.
The second reason diverts domestic contradictions
Don't look at Liu Bei's coming to Sichuan for many years, but it doesn't mean how convincing the local forces and other forces are. Especially after Liu Bei's death, several forces within the Shu Han Dynasty restrained each other and contradicted each other. At the same time, the internal rebellion continued, and it can be said that Zhuge Liang's pressure was not small.
For this point, in fact, not only Zhuge Liang, many times the ruler will transfer domestic contradictions in this way. External threats can improve domestic cohesion and reduce the attrition caused by internal contradictions. At the same time, if you win, it will be a good thing for the whole country.
The third reason could not make Cao Wei bigger
In fact, during the Three Kingdoms period, Cao Wei itself was the largest, and everyone knew this. The Shu Han and Eastern Wu were probably not rivals.
Didn't Zhuge Liang know? He was clear. But in the long run, if Cao Wei is allowed to engage in economic and military affairs in a down-to-earth manner, then Cao Wei can only be more powerful, and there will really be no way to do it at that time.
Therefore, Zhuge Liang could only adopt the strategy of attacking instead of defending, both weakening Cao Wei's strength and thinking of developing himself. Because since it was the Northern Expedition, it was impossible for one's own country to be invaded, so it was not to develop oneself and destroy others.
However, objectively speaking, the impact of the Five Northern Expeditions on Shu Han was very large, especially brought serious economic burdens to Shu Han.