In the sixteenth year of Jian'an (211), Liu Bei entered Shu and allied with Liu Zhang, Yizhou Mu in Fucheng, where the two sides gathered for more than 100 days, after which Liu Zhang returned to Chengdu, and Liu Bei went north to crusade against Zhang Lu.

However, only a year later, Liu Zhang and Liu Bei turned against each other, and the two met each other.

【Fucheng Alliance】

Long before Liu Bei entered Shu, he had a very detailed understanding of the geography and situation in Shuzhong through Zhang Song, Fa Zheng and others. According to the "Book of Wu", Liu Bei met with Zhang Song earlier, and later received Fa Zheng, both of whom were gracious and accepted, and did their best to be a landlord. Liu Bei also asked them about the geographical environment of Shuzhong, the number of people in the weapon warehouse, and the distance of other key roads, Zhang Song and others explained to Liu Bei in detail, and also drew some maps of mountains and rivers for Liu Bei's reference, so Liu Bei was able to understand the reality of Shu.

Therefore, Liu Bei's entry into Shu itself is ill-intentioned, of course, Liu Zhang's classmates are also playing his own small calculations, wanting Liu Bei to help him fight against Zhang Lu and Cao Cao, the so-called politics itself is such a thing.

In the sixteenth year of Jian'an (211), Liu Bei set out from Jingzhou to the north of Jiangzhou, and then arrived at Fuxian by the Dianjiang waterway, which was only 360 miles away from Chengdu. And Liu Zhang led more than 30,000 infantry and cavalry, chariots and curtains, dazzling, to meet Liu Bei, Liu Zhang himself personally went out of the city to greet him; Liu Bei's soldiers also greeted them in turn, and the two were very happy to see each other, and everyone gathered for more than 100 days.

At that time, Zhang Song sent an envoy Fa Zheng to inform Liu Bei, hoping that Liu Bei would take the opportunity to get rid of Liu Zhang and occupy Yizhou. Liu Bei said: "This is a big deal, don't be in a hurry." After Pang Tong followed Liu Bei to lead the troops into Shu, he also offered advice to Liu Bei at this time: "Take the opportunity of today's meeting to seize Liu Zhang, so that the general can sit in Yizhou without having to work and mobilize the people." Liu Bei said: "I have just entered another country, and the prestige of kindness has not yet been established, so this kind of thing cannot be done." ”

Liu Bei rejected the proposal of Zhang Song, Pang Tong and others, and gathered with Liu Zhang in Fucheng for 100 days, and finally got together and dispersed. Liu Bei did this at that time is actually very understandable, when the alliance seems to be a great opportunity to get rid of Liu Zhang, but in fact, Liu Zhang led more than 30,000 troops at that time, and Liu Bei was obviously not defenseless, and Liu Zhang was a landlord, how could it be so simple for Liu Bei to start? And just like Liu Bei said, if he makes a move on Liu Zhang at this time, no matter what, it will definitely deal a big blow to his reputation, in case of failure, Liu Bei himself may have to get in, and the possibility of Liu Bei's failure is not low.

All in all, choosing to do it to Liu Zhang when he met the alliance in Fucheng only seemed to be a good suggestion, but in fact, while the return was high, the risk was extremely high and the success rate was extremely low.

In this case, Liu Bei completely gave up on Liu Zhang from the beginning, but gathered with him for a hundred days, which seemed stupid, but in fact it was very clever, first of all, Liu Bei completely won Liu Zhang's trust, the reason why Liu Zhang chose to meet Liu Bei was, in the final analysis, to see in person whether Liu Bei could be trusted, and Liu Bei completely gave up his malice towards Liu Zhang at this time, which dispelled Liu Zhang's doubts, and made Liu Bei himself get a large amount of material support.

On the surface, the Fucheng Huimeng was extremely successful, and Liu Zhang recommended Liu Bei to act as the Great Sima and concurrently serve as the lieutenant of the school; Liu Bei also elected Liu Zhang to act as the general of Zhenxi and concurrently serve as the pastor of Yizhou. Liu Zhang added troops to Liu Bei, asked him to attack Zhang Lu, and made him supervise the soldiers and horses at Baishui Pass. Liu Bei finally gathered more than 30,000 soldiers and horses from all walks of life, and the chariots, armor, weapons, grain and grass materials were very abundant.

At that time, Liu Zhang provided Liu Bei with a large number of materials and asked him to crusade against Zhang Lu, and then the two said goodbye. According to the "Book of Wu", Zhang used 200,000 meters of rice, thousands of horses, thousands of cars, and brocade silk to send Liu Bei.

【Take the opportunity to get oil】

After Liu Bei went north to Jiameng, he did not immediately attack Zhang Lu, but spread kindness and won the hearts of the people. In the following year (212), Cao Cao conquered Sun Quan, and Sun Quan asked Liu Bei to come to the rescue, but Liu Bei not only did not send troops to support Sun Quan, but took the opportunity to ask Liu Zhang to help Guan Yu in Jingzhou.

At that time, Liu Bei sent someone to inform Liu Zhang: "Cao Cao's expedition to Wu, Eastern Wu is very critical. Sun and I are in a lip-to-tooth relationship, and Le Jin is holding on to Guan Yu in Qingni, if he doesn't go to rescue Guan Yu now, Le Jin will win a complete victory, and then turn his head to invade Yizhou, and his worries are much more than Zhang Lu. Zhang Lu is just a thief who divides one side, so there is no need to worry too much. So he asked Liu Zhang for 10,000 soldiers and horses and a large amount of grain and grass supplies, but Liu Zhang only promised to send an additional 4,000 men, and only half of everything else.

【Anti-Eye】

In the seventeenth year of Jian'an (212), Zhang Song wrote to Liu Bei and Fa Zheng urging them to act in time, saying: "Now that the big thing is about to succeed, how can you give it up? And Zhang Song's elder brother Guanghan Taishou Zhang Su knew about this incident, and was afraid that it would harm him, so he revealed Zhang Song's conspiracy to Liu Zhang. So Liu Zhang arrested and killed Zhang Song, which directly caused Liu Bei and Liu Zhang to have a grudge.

Zhang Su is Zhang Song's elder brother, when Cao Cao went south to Jingzhou, Liu Zhang sent envoys three times to meet Cao Cao, the second time he sent Zhang Su, Zhang Su was also named Guanghan Taishou, the third time was Zhang Song's envoy, but he got nothing, so he complained about Cao Cao, and persuaded Liu Zhang to break off relations with Liu Bei, but secretly helped Liu Bei seize Yizhou.

According to the "Miscellaneous Records of the Elderly", Zhang Su has a majestic appearance and a great appearance. Loose is short, debauched and disciplined, but he knows the essence and is talented. Liu Zhang sent Cao Gong, but Cao Gong was not very polite; The princess book Yang Xuan (that is, Yang Xiu) is deep, and the white public is loose, and the public does not accept it. The military book written by the public office shows the pine, and the pine feast and drink will be recited at a glance. This is a different way.

Historically, the relationship between Zhang Song and Fa Zheng is similar to the relationship between Gao Shun and Zhang Liao, originally Zhang Song's status within the Yizhou Group was much higher than that of Fa Zheng, Fa Zheng was very unhappy at the beginning, it was Zhang Song who appreciated him and persuaded Liu Zhang to hand over the task of envoy to Jingzhou to Fa Zheng, and Fa Zheng thus entered Liu Bei's field of vision, and was finally reused by him.

When Liu Bei sought to win Yizhou, Zhang Song, as Liu Bei's internal response, was much more important than Fa Zheng, but Zhang Song's classmates sacrificed early for Liu Bei, and Fa Zheng was radiant later, and then overtook Zhang Song in terms of historical status, which is the same as Gao Shun's death, Zhang Liao made contributions to Cao Wei, and his status was the same.