Cao Cao was worried that Liu Bei would seize Jiangling, so the army went south to Xiangyang, and learned that Liu Bei had set off, so he personally led 5,000 elite cavalry to pursue rapidly, marching more than 300 miles in a day and night, and caught up with the emperor's uncle when he reached the county magistrate. At that time, although Liu Bei had a large number of people, most of them were ordinary people, and the team was huge but not strong, and he was completely unable to resist Cao Cao.

Although this battle ended in Liu Bei's fiasco, there are also records of Zhao Yun saving Adou and Zhang Fei drinking to stop Cao Jun, and Xu Shu also left Liu Bei at this time.

【Escape from Dangyang】

In the thirteenth year of Jian'an (208), Cao Cao took Cao Chun and other soldiers to conquer Jingzhou in the south, and Liu Cong was forced to surrender. Later, Cao Cao heard that Liu Bei was going south, and he was afraid that he would get the Jiangling army, so he gave up his baggage, and Cao Chun led the tiger and leopard to ride 5,000 miles, and caught up with Liu Bei at Changsaka at a speed of 300 miles a day, defeated him and captured countless baggage, and surrendered Liu Bei's scattered soldiers.

At that time, Liu Bei heard that Cao Cao had suddenly arrived, left his wife and children and fled by himself, and ordered Zhang Fei to lead 20 cavalry to break the rear. Zhang Fei guarded the river bank and demolished the river bridge, his eyes widened angrily, and he shouted with a spear in his hand: "I am Zhang Yide, who dares to come and fight me to the death!" No one dared to approach Cao's army, so Liu Bei and the others were able to escape.

At that time, Zhao Yun held Liu Bei's youngest son, the later lord Liu Chan, to protect Mrs. Gan, that is, Liu Chan's mother, and sacrificed her life to save their mother and son from death.

According to the record of "Yun Farewell Biography", after Liu Bei's army was defeated, Zhao Yun went to the north, and someone said to Liu Bei: "Zhao Yun has fled north." Liu Bei was furious, threw his halberd at the man, and said, "Zhao Zilong will not leave me and run away." After a while, Zhao Yun came with Liu Bei's son Liu Chan in his arms.

Dangyang fiasco, Liu Bei just barely kept his own safety, originally Xu Shu and Zhuge Liang went south with Liu Bei, but there were too few people who could escape in this battle, Xu Shu's old mother was captured by Cao Cao's army, so Xu Shu went to see Liu Bei, said goodbye to Liu Bei, pointed to his heart and said: "I originally planned to establish the great cause of the king with the general, it is to rely on this square inch of land, now I have lost my mother, the square inch has been chaotic, and it is useless to stay, please separate from the general from now on." Xu Shu left Liu Bei and returned to Cao Cao with Shi Tao.

Later, Liu Bei and others rendezvoused with Guan Yu's fleet, were able to cross the water, met Liu Qi and more than 10,000 people led by him, and arrived at Xiakou with Liu Qi. After Liu Bei lost this battle, he lost the opportunity to control Jiangling, and Cao Cao took advantage of the situation to enter Jiangling, and Jingzhou had basically fallen into his hands.

【Xu Shu's inflated historical status】

In "Romance of the Three Kingdoms", Xu Shu was the first important strategist Liu Bei get, helping him break through the Eight Gates Golden Lock Array, take Fancheng directly, and defeat Cao Ren, which can be said to be majestic and impressive. Later, Cheng Yu, an important strategist under Cao Cao, evaluated Xu Shu as ten times his talent, so Cao Cao hijacked his mother and forced her to submit to him.

And Xu Shu had no choice but to take refuge in Cao Cao, but before he left, he recommended Zhuge Liang to Liu Bei as his successor, and what happened then was the well-known Sangu Thatched House.

It can be said that in "Romance of the Three Kingdoms", Zhuge Liang is Xu Shu's replacement, and Xu Shu's own talent is almost not inferior to Zhuge Liang, so Xu Shu's evaluation in later generations is also extremely high, and he is considered one of the few top strategists at that time.

But in the official history, Xu Shu's status and ability cannot be compared with Zhuge Liang at all.

First of all, Zhuge Liang is not a replacement for Xu Shu, Xu Shu did recommend Zhuge Liang to Liu Bei, but Xu Shu had not left Liu Bei at that time, after Liu Bei invited Zhuge Liang, the two assisted Liu Bei together, after Zhuge Liang came and Liu Bei were like fish in water, and his status was significantly higher than that of Xu Shu, so Zhuge Liang was never a substitute for Xu Shu, Xu Shu was just Zhuge Liang's recommender. This is completely different from Cao Cao finding Guo Jia to replace Xi Zhicai, and Xun You to replace Xun Yu.

Secondly, Xu Shu's ability in history was not outstanding, the only thing he did by Liu Bei's side was to recommend Zhuge Liang to Liu Bei, Liu Bei was able to defeat Xiahoudun also relied on himself, and Xu Shu probably hadn't taken refuge in Liu Bei at that time.

And Cao Cao didn't specifically target Xu Shu at that time, capturing his mother, just catching it, Cao Cao probably hadn't heard of Xu Shu's name at that time, Cheng Yu commented that Xu Shu's talent was ten times better than it, which was completely the plot of the novel.

Although Xu Shu left Liu Bei because of his old mother, it is undeniable that when Xu Shu left, Liu Bei was in an absolute predicament and was in need of help, and at that time Cao Cao had just occupied Jingzhou and was in full swing, and Xu Shu's departure at this time was a great harm to Liu Bei.

In the end, Xu Shu is generally not a figure in Liu Bei's camp like Chen Deng, although they have all taken refuge in Liu Bei, they have obviously worked in the Cao Wei Group for a longer time.

After Xu Shu took refuge in Cao Cao, he did not show much outstanding ability, and there are not many records about it, in the fourth year of the early Huang Dynasty (223), Xu Shu was appointed as the right middle general and the imperial history in the Wei state.

In the second year of Taihe (228), Zhuge Liang led the army on a northern expedition, and heard that Xu Shu and Shi Tao (county guard, Diannong captain) were not very high, so he sighed: "Could it be that there are too many strategists in Wei, why not reuse Xu Shu and Shi Tao?" ”

Overall, Xu Shu's historical status is much higher today.

【Defeat of the Sun】

After the fiasco of Dangyang, Liu Bei's plan was completely disrupted, and the emperor's uncle was originally ready to occupy Jiangling before Cao Cao, seize where the materials were, and use this as a base to fight against Cao Cao, but Liu Bei did not expect his reputation to be so high, and the nearby people and scholars actually came to vote, which greatly slowed down the speed of the march, and Liu Bei himself was too merciful, so he had to go south with the large army, and did not quickly occupy Jiangling first, resulting in Cao Cao's inability to fight after chasing him, and he was defeated in one fell swoop.

Liu Bei needs to bear the main responsibility for losing this battle, and his benevolence not only harms himself, but also harms the people and scholars who follow him.

But on the other hand, it also reflected Liu Bei's great prestige in Jingzhou at that time. However, the people and scholars will come to Liu Bei, in addition to Liu Bei's own attraction and influence, there is also Liu Cong's unpopularity, coupled with the fear of the people of Jingzhou for Cao Cao, after all, Cao Cao did not do anything less at that time, and also implemented a strict policy of tuntian, crazy exploitation of the people, and the reputation will be greatly affected.

But then again, in the Three Kingdoms era, there was only Liu Yu who won the hearts of the people to this extent, except for Liu Bei.