At the end of the Eastern Han Dynasty, there was a situation in which thirteen states were divided. According to statistics, Cao Wei monopolized 95 states, Soochow occupies 25 states, while Shuhan only owns 1 state of Yizhou. However, Shu Han, under the leadership of Liu Bei and Zhuge Liang, was still able to fight externally with a strong offensive, while launching an offensive against Cao Wei and not showing weakness to Sun Quan. So, how did Shu Han maintain such a strong combat power? First of all, Yizhou's unique character is particularly prominent. Although it was only a state, during the Three Kingdoms period, it was much larger than the average state. Taking population as an example, the total population of Kyushu in the Central Plains is 4.5 million, with an average of about 500,000 people in each state, while Yizhou has reached 940,000, which can be said to be one state to two states. In addition, Yizhou did not experience large-scale wars during the Three Kingdoms period, and despite the invasion of Zhang Lu and Liu Bei's entry into Sichuan, the scale of the war was extremely limited.
Chengdu, in particular, has maintained a long period of peace and stability, and while Kyushu in the Central Plains fell into a state of half-decay, Yizhou still maintained its full vitality. Yizhou also has a significant advantage, that is, its geographical location is easy to defend and difficult to attack, which provides a fairly safe base camp for Shu Han. Compared with Kyushu and Jingzhou in the Central Plains, this is the most prominent advantage of Shu Han, and it also determines that Shu Han can boldly fight abroad, if it can be defeated, it will be defeated, and if it can't be defeated, it will retreat, as long as it can be successfully evacuated, it will not cause great harm. Secondly, Shu Han's talents are extensive. On the surface, Shu Han could only select talents from Yizhou's population of 940,000, which seemed to be at a disadvantage compared to Cao Wei's talent selection from the 4.5 million population of Kyushu in the Central Plains. However, this was only the mode of competition at the end of the Three Kingdoms. For the most part, Shuhan's talents are not limited to Yizhou, but come from all over the world.
For example, Zhuge Liang was a native of Shandong, and only later moved to Jingzhou, and eventually entered Sichuan with Liu Bei; The five tiger generals of Shu Han, Guan Yu, Zhang Fei, Zhao Yun, Ma Chao and Huang Zhong, none of them were natives of Yizhou; Jiang Wei, Wei Yan and Wang Ping are also talents from other places. The fundamental reason is that Liu Bei himself is an external force, and he brought talent elites from all over the world into Yizhou. In this way, the talent density of Shu Han is unusually high, in a sense, it is a bit like the United States today, although the population is only 300 million, but its talent source is the global elite, which is also the real terrible thing about Shu Han. Third, Liu Bei took the banner of the "Han Dynasty" as an advantage. In the turbulent times at the end of the Eastern Han Dynasty, in order to gain a firm foothold, all the princes must have outstanding features, such as Cao Cao's "coercing the Son of Heaven to order the princes", Yuan Shao's rule of Qing, You, and Sanzhou, and Sun Quan's Jiangdong Naval Army.
And Liu Bei's Shu Han, its advantage lies in the banner of "Han Family". The main reasons why Shu Han was able to maintain such a strong strength can be summarized in four points. The first is the unique geographical conditions of Yizhou, the second is the talent support from all sides, then the symbolism of the Han flag, and finally the outstanding personal ability of Zhuge Liang. In fact, the title "Wei Shu Wu" is not accurate, and a more appropriate term should be "Wei Han Wu", because the real country name of Shu Han is "Han", not "Shu". Before Cao Pi usurped the Han Dynasty, Liu Bei used the slogan of "Kuang Fu Han Room" as the banner, and after Cao Pi usurped the Han Dynasty, Liu Bei decisively proclaimed himself emperor in Yizhou, nominally "inheriting the great unification", and successfully established Shu Han as the "orthodox teacher". These flags may have been just a symbol for Cao Cao and Liu Bei, but for the middle-level cadres and front-line soldiers of the army, they were a reason to stimulate strong combat effectiveness.
Before the Battle of Yiling, the reason why Shu Han was so violent, the reasons mentioned earlier are enough to explain clearly. However, after the Battle of Yiling, the advantages of Shu and Han were quickly lost, the foundation of Yizhou's long-term peaceful accumulation was exhausted, most of the talents from all over the world were lost, and the significance of the "Han Family" banner was gradually weakened. Just when Shu Han was in a slump, Zhuge Liang stepped forward, reorganized a new army in a short time, and resolutely launched five northern expeditions to attack instead of defend, and used Yizhou infantry to fight against the Yongliang cavalry, and achieved brilliant achievements such as the victory of Lucheng and the shooting of Zhang He. After Zhuge Liang's death, Jiang Wei, Wang Ping, Jiang Wan, Fei Yi and others continued to maintain Shu Han and continue Zhuge Liang's legacy. In short, Yizhou's geographical conditions, talent support from all sides, the symbolism of the Han flag, and Zhuge Liang's outstanding ability all contributed to the strength of Shu Han.
Especially after the Battle of Yiling, although the general trend has gone, under the rule of Zhuge Liang, Shu Han was still able to conquer Cao Wei in the north and barbarians in the south, almost forcibly extending the life of the entire Shu Han for 30 years with his own strength. In Chinese history, apart from Zhuge Liang, I am afraid it is difficult to find a second figure who can be compared.