Jingzhou and Hanzhong are very important to Shu. Why?

I use a proportion to describe the importance of Jingzhou and Hanzhong to Shu Han.

Hanzhong is the "helmet" of Shu Han. Without Hanzhong, Shu Han's brain will be attacked by the outside world, while Jingzhou is Shu Han's "right-hand man". Without Jingzhou, Shu Han will lose an arm and the ability to expand overseas.

First, Hanzhong

The core area of Shuhan is Yizhou, which is today's Sichuan Pandi, including Sichuan, Chongqing, Yunnan and Guizhou. The core area is Chengdu Plain, and Hanzhong is the gateway to the north of Yizhou. It is said to be a gateway because Hanzhong is a place of throat from Guanzhong to Yizhou. Whoever controls Hanzhong will control the throat of Shu.

In the same way, from Yizhou to the north, you must pass Hanzhong first, and then Zhuge Liang went north. Hanzhong is the base camp of the Northern Expeditionary Army. All Zhuge Liang's personnel, equipment and materials were assembled in Hanzhong and then transported to the front through Hanzhong. There are five roads from Hanzhong to Guanzhong or Longyou Post, namely Qishan Road, Chencang Road, Xiexie Road, Luo Luo Lu and Woods Valley Road.

Hanzhong is the south of these five roads, and the intersection of Guanzhong and Longyou is the north. Hanzhong plays a connecting role. Without Hanzhong, Shu Han was strangled, unable to expand abroad, and in danger of national subjugation at any time. Therefore, shortly after Liu Bei won Yizhou, Fazheng suggested that Liu Bei take Hanzhong.

Although Liu Bei's attack on Hanzhong exhausted all the resources of Yizhou and reached the point where the man was the master and the woman was the master, Liu Bei was still determined to win, which was beyond the measure of money and manpower. Hanzhong has a strategic position in Shu Han. Liu Bei's ideal is to unify the world and return to his old capital, so he must win Hanzhong.

The demise of Shu Han was also due to the loss of Hanzhong. In 263 AD, Wei attacked Shu, and Wei Jun's main force entered Hanzhong. Although Seoul, Lecheng and Huang Jincheng have to fight hard, the whole Hanzhong is surrounded and occupied by Wei Jun. If Hanzhong falls, even if Yizhou still has the ability to resist, it will be a disaster. Even without Wargo's smuggling, a level playing field forced Liu Chan to fall, and the demise of Shu Han would not be too far away. This is the role of Hanzhong.

Second, Jingzhou

Jingzhou is the right-hand man of Shu Han. If Shu Han only wants a peaceful corner, then Jingzhou is dispensable. If Shu and Han want to unify the world, they must take Jingzhou as a strategic location. The geographical location of Jingzhou is very important, connecting the preceding with the following.

To the north of Jingzhou is Xiangfan, which is Nanyang county controlled by Cao Wei, to the south of Jingzhou are the Yangtze River and Jingnan counties, to the east of Jingzhou is Jiangdong Sunquan, and to the west of Jingzhou is Yizhou. If Xiangfan is the thoroughfare of seven provinces and Jingzhou is the thoroughfare of five provinces, the traffic is very convenient.

For Shu Han, Jingzhou's main function is the base of progress, which is the place where Zhuge Liang said that war was going on. For Longzhong, the world has changed, and Hanzhong and Jingzhou sent troops to the Northern Expedition. Relatively speaking, Jingzhou invasion is more convenient and the geographical conditions are better. Hanzhong is difficult to invade and the road is difficult to pass.

It is precisely because Jingzhou is the right-hand man of Shu Han, so once Jingzhou fell, Shu Han fell into a weak position. Since Guan Yu lost Jingzhou, Shu Han inevitably fell into a weak position. It has been developing at a high speed until now. This is the difference. Without the right arm, it is natural to decline, including the battle of Yiling initiated by Liu Bei later, and because Jingzhou was finally defeated, Shu Han lost the power to compete for the world forever. This is the role of Jingzhou.

Jingzhou and Hanzhong, together, are the strength of Shu Han to dominate the world, and no one can compete for the world.