In the battle of Xiangfan, after Liu Fengmeng refused to reinforce Guan Yu, Mengda was afraid that Liu Bei would be held accountable, which led to conflict with Liu Feng and defected to Cao Wei. With the support of Cao Wei, he captured Shang Yong. Cao Pi merged the three counties of Fangling, Shang Yong and Xicheng into a new city, and made Mengda lead the new city as a satrap. After Cao Pi's death, Meng Da lost help in the dynasty and was lured by Zhuge Liang to betray Cao Wei. Mengda was destroyed by Sima Yi, who knew the situation and quickly attacked and cut it. From then on, Shang Yong was under the jurisdiction of Cao Wei. Is Shang Yong actually occupied by Liu Feng and Meng Da crucial to Shu Han? The following is a brief analysis based on relevant information.
Firstly, it analyzes the general situation of Shang Yong.
Shang Yong is located in Zhushan County, Shiyan City, Hubei Province. The environment in this area is surrounded by mountains, and a Han River runs through it and flows into the Yangtze River. If you go downstream from Shang Yong, you can go straight to Xiangyang, the throat town. It can be said that Shang Yong is located in the border area of Wei Shuwu, which is a very critical position and became a battleground for military strategists at that time. The place name record records:
The ground is flat, so it is called Shang Yong, which is a ladder to mend the sky. It is located 70 miles west of Shangyong in Zhushan County.
From here, we can see that the terrain in Shang Yong is dangerous and solid. Therefore, when attacking Shang Yong, Liu Bei was afraid that Mengda's 4,000 elite troops could not be defeated, and he also sent Liu Feng to lead the troops to support him, which shows that Liu Bei attached great importance to Shang Yong.
Secondly, Shang Yong is the link between Jingzhou and Hanzhong, which is very important to Shu.
So, why did Liu Bei attach so much importance to Shang Yong? This is because of Shang Yong's unique geographical environment. Shang Yong is surrounded by mountains and is in danger, but there is a waterway. At that time, waterway was the best mode of transportation. In this way, Jingzhou and Hanzhong can be linked by the waterway of Hanshui River. Guan Yu attacked Xiangfan and seized the opportunity when Cao Cao wanted to return to Guanzhong. More importantly, when Liu Feng and Meng Da captured Shang Yong, they sent troops to attack Xiangfan.
At that time, the strategic situation of Shu Han in Jingzhou was not good. Wu Dong, four counties in the south of the Yangtze River were cut by Wu Dong. Guan Yu's fundamental stronghold is separated from Wu Dong by a river, and there is no strategic depth. And Xiangyang and Jiangling are integrated. Someone commented? The Jiangling trail in Xiangyang is 400 miles, so you can't go to Xiangyang. Jiangling can't stand the attack. ?
Therefore, Guan Yu seized this fleeting best fighter and launched the battle of Xiangfan. In the early stage of the campaign, Guan Yu flooded the Seventh Army, which greatly shocked China and achieved brilliant results. However, the contradiction of insufficient troops is gradually emerging.
Guan Yu turned to Liu Feng and Meng Da for help many times. Did Liu Feng and Meng Da? Are you unshakable when you first come to Shanxian County? The reason for refusing Guan Yu's request led to Guan Yu's downfall. This is also where Liu Bei later resented Liu Feng and Meng Da.
At that time, if Guan Yu took Xiangfan, his connection with Xichuan would be more than just a waterway of the Yangtze River. He got rid of the threat of Soochow completely. Even if Wu Dong wins Jiangling Public Security, he can also contact Hanshui to give up. In this way, Guan Yu's Jingzhou and Xichuan are completely unified, and Guan He can attack and retreat and defend. In this case, Wu Dong also dare not easily defeat the alliance. Because they can't kill Guan Yu, Guan Yu has strategic depth and solid communication lines.
Said Man Chong advised Coss out of Fancheng, saying:
(full) pet:? The scenery is changing rapidly, I hope it won't be long. Yu Wen has sent other generals to the south, and the people are disturbing them. Those who dare not go are afraid that our army will slap their ears. Escaped today, there will be no country south of the Red River. You should treat it. ?
If Coss gives up Fancheng, Cao Wei will lose a lot and Guan Yu will have a better strategic situation. Unfortunately, Liu Da was short-sighted and didn't have a big picture. He refused to reinforce Guan Yu when he needed support most. At that time, even if all the troops were sacrificed, it was worthwhile to win Xiangfan.
Zhuge Liang's attention to Shang Yong also shows its importance.
In the later time, Shang Yong entered the era of obscurity. Mengda's rebellion was just a flash in the pan. During the first Northern Expedition, Zhuge Liang induced Mengda to rebel. When Mengda hesitated, Zhuge Liang sent a double agent to leak the news of Mengda's rebellion, forcing Mengda to rebel. Meng Da was wiped out in ten days under Sima Yi's attack.
Thus, Zhuge Liang did not regard Shang Yong as the starting point of the Northern Expedition at all. He only used Meng Da's rebellion to attract the attention of Cao Wei and detained Cao Wei's army in Kanto to relieve the pressure of his northern expedition. We can see that Shang Yong has lost its strategic value in Zhuge Liang's eyes.
After Shang Yong fell into the hands of Sima Yi, Cao Wei organized an attack on Shu Han in the fourth year of Taihe. Cao Wei's troops were divided into three roads, and Shang Yong became the starting point of Cao Wei's first attack. History:
(Taihe) In four years, he moved the general, increased the viceroy, and made a holiday to attack Shu with Cao Zhen. The emperor opened the way from Xi Mountain in Xicheng, and went hand in hand with land and water. As for Mount Xi, he withdrew from Xinfeng County. The troops are in Kou Dan, and when it rains, they will move the troops.
We can see that it is difficult for Cao Wei to attack Shu Han from Shang Yong. When Shu Han got the power of Jiang Wan, he also wanted to attack Shang Yong. History:
Jiang Wan was a boatman in the Han Dynasty who wanted to attack Wei Xin and Shang Yong. If you have an old illness, you can do it as early as possible. But many people say that if you can't get ahead, it's hard to get back to your roots, which is not a long-term solution.
In a word, from the utilization and evaluation of Shang Yong by Cao Wei and Shu Han, we can see that due to the unique geographical environment of Shang Yong. Land and mountain roads are difficult and dangerous, and waterways are smooth and convenient. Shu Han is located in the upper reaches, so it is difficult to retreat. Therefore, as the attack direction of Cao Wei, it is inappropriate and difficult to achieve its goal.
Although it is easier for Shu Han to win Shang Yong, Shang Yong is good at defense. If he continues to attack, he will encounter the important place of Xiangfan in Cao Wei. It is almost impossible to win Xiangfan, which is heavily guarded by water. Therefore, if Jingzhou is in the hands of Shu Han, Shang Yong is an extremely important strategic location, which can assist Xiangfan and communicate the connection between Xichuan and Jingzhou.
However, without Jingzhou, Shang Yong will lose its strategic significance. Shang Yong is a vast country with few people and things, so occupying it has no strategic value for Shu Han. Therefore, after the loss of Jingzhou, Zhuge Liang and the later rulers of Shu and Han paid no attention to Shang Yong, who lost its strategic value.