In the south, in addition to Zhang's father and son, Jiaozhou Mu Zhang Jin is also one of Liu Biao's enemies, but relatively speaking, Zhang Jin is still relatively easy to deal with.

But on the contrary, Cao Cao in the north can be said to be the strongest enemy faced by Liu Biao, Cao Cao's group crusaded against the Nanyang area of Jingzhou four times, but in vain, and then lost Nanyang because of Zhang Xiu's surrender, but before Liu Biao's death, Cao Cao had annexed the four northern states and became the lord of the north at that time.

【Jiaozhou Mu Zhangjin】

Zhang Jin turned out to be a disciple under Yuan Shao, who had sent him to persuade the general He Jin to deal with the Ten Standing Servants. Therefore, Zhang Jin and Liu Biao were both close to Yuan Shao, but unlike Liu Biao, Zhang Jin was not Yuan Shao's ally later.

Later, after the victory of Guandu, Xiahoudun once wrote a letter to Shi Wei, which read: "Grant Sun Ben to Changsha, and Zhang Jin to zero and Gui." ”

This suggests that Cao Cao may have co-opted Zhang Jin and Sun Ben to contain Liu Biao in order to alleviate his own external pressure when he confronted Yuan Shao, and that Zhang Jin may have later started a war with Liu Biao for this reason.

In addition, according to the "Southern Grass-Like, Juanzhong, Woody", Zhang Jin once produced zongzi made from Yizhizi in Jiaozhi County and Hepu County in the eighth year of Jian'an (203) to pay tribute to the imperial court, and it can be seen that the relationship between Zhang Jin and Cao Cao at that time should have been at least not bad.

The time of hostility between Zhang Jin and Liu Biao roughly began in the fourth year of Jian'an (199), which was similar to the time of Zhang Xian's rebellion, so Zhang Xian was most likely not alone at that time, and there was Zhang Jin's support and Cao Cao's cheering. It's just that Jiaozhou at that time was far from being developed, so the strength was quite disparity with other large states, after Zhang Xian's death, his son Zhang Yi was eliminated by Liu Biao, Zhang Jin also began to be completely disadvantaged in the battle with Liu Biao, and finally Zhang Jin was killed by the generals.

The unfavorable situation was only one of the reasons why Zhang Jin was killed, Zhang Jin was one of the few religious madmen at that time, he ignored the teachings of the sages and the laws made by the state, wrapped a red turban cloth on his head, played the piano and burned incense, and was very obsessed with Taoist scriptures, which made the people around him unhappy, and he was also very loose in both restraint and supervision, without authority, and his subordinates even began to leave him without permission.

After Zhang Jin's death, Liu Biao did not miss the opportunity, he sent his subordinate Lai Gong to serve as the assassin of Jiaozhou, and he appointed his subordinate Wu Ju as the Taishou of Cangwu, in order to replace Shi Huang, who had just died of illness, and preemptively appointed officials in the imperial court to occupy Jiaozhou first.

Although the Xuchang court was a step late, Cao Cao, in order to prevent Liu Biao from getting Jiaozhou, appointed Jiaozhi Taishou Shixie, a native faction of Jiaozhou, as "Suinan Zhonglang General, Governor of Seven Counties, and Jiaojiao Taishou as before" to fight against Liu Biao.

Later, Wu Ju had a conflict with Lai Gong and expelled Lai Gong from Jiaozhou, and Liu Biao's plan to include Jiaozhou in his sphere of influence failed.

【Yuan Shu occupying Nanyang】

Yuan Shu was the first enemy Liu Biao faced during the Qunxiong era, when Yuan Shu occupied Nanyang County, a large northern county in Jingzhou, and won the war against Dong Zhuo, and repelled the invasion of Yuzhou by Zhou Ang, and was the most popular prince at that time.

Liu Biao became an enemy with Yuan Shu because he chose to help Yuan Shao, when Yuan Shu sent the general Sun Jian south, Liu Biao's army was in a difficult situation for a while, but God blessed, Sun Jian died because of the loss, which made Liu Biao easily victorious, and then Yuan Shu failed in the crusade against Yanzhou and left Jingzhou, and Nanyang County was also taken back by Liu Biao.

【Mighty Cao Cao】

After Yuan Shu left, the situation in the north of Liu Biao improved for a while, but after Cao Cao became bigger, the situation became bad again.

Yuan Shao, Liu Biao and Cao Cao were originally allies, but after Cao Cao "coerced the Son of Heaven and ordered the princes" and moved the capital to Xuchang, his prestige increased greatly, and he began not to take Yuan Shao and Liu Biao in his eyes, because Nanyang County was close to Xuchang, so he was regarded by Cao Cao as a thorn in the flesh, and sent a large army to crusade several times, and Liu Biao used Zhang Xiu as a northern barrier to fight against Cao Cao.

In the second year of Jian'an (197), Cao Cao attacked Nanyang for the first time, this time Zhang Xiu surrendered without a fight, but later because Cao Cao forcibly occupied Zhang Xiu's aunt, and dug Zhang Xiu's subordinate general Hu Che'er, which angered Zhang Xiu, so he rebelled, resulting in Cao Cao's eldest son Cao Ang, love general Dian Wei and nephew Cao Anmin all died in Wancheng. After that, Zhang Xiu chose to unite with Liu Biao again, and Liu Biao saw that Cao Cao had suffered such a heavy loss in Wancheng, and did not think that Zhang Xiu would take refuge in Cao Cao again, so he accepted him.

After Cao Cao's defeat, Nanyang and Zhangling rebelled against Cao Cao and attached themselves to Zhang Xiu and Liu Biao, and Cao Cao sent Cao Hong to crusade, but without success.

In October of the same year, Cao Cao personally sent troops to attack Nanyang again, defeated and captured Deng Ji, a general under Liu Biao, alive, and occupied Huyang and Wuyin, but did not succeed in capturing Nanyang and eliminating Zhang Xiu.

In the third year of Jian'an (198), Cao Cao personally led the army to crusade against Zhang Xiu for the third time, and surrounded it in the city, after which Liu Biao sent reinforcements to the north, and at the same time spread the news that Tian Feng persuaded Yuan Shao to go south to Xuchang to seize the Son of Heaven, Cao Cao then retreated, but was blocked by the combined forces of Liu Biao and Zhang Xiu, and Cao Cao was able to return to Xuchang after defeating it.

For a time, Cao Cao's southward momentum was curbed.

But what people didn't expect was that Zhang Xiu actually defected to Cao Cao again under the persuasion of Jia Xu, and Nanyang, the gateway to Jingzhou, was no longer owned by Liu Biao.

Liu Biao will lose the Nanyang area can be said to be self-seeking, Zhang Xiu was just a remnant of the new loss of the owner, Liu Biao handed over his northern county to him almost in vain, and at the same time he did not have enough restraints, resulting in Zhang Xiu becoming the actual master of Nanyang, if it were not for Cao Cao's own death, Nanyang County would have been lost, and then Liu Biao's control over Zhang Xiu was still weak, Yuan Shao sent a messenger to bypass Liu Biao to win over Zhang Xiu.

Therefore, although Liu Biao gave Zhang Xiu a lot of support, Zhang Xiu never regarded himself as a part of the Jingzhou Group, even if he did not defect to Cao Cao in the future, he would also take refuge in others, Nanyang was doomed to lose from the moment Liu Biao handed it over to Zhang Xiu.

And get Nanyang, after Guandu defeated Yuan Shao, Cao Cao's threat to Liu Biao increased day by day, and he was one of Liu Biao's main enemies at that time, and then Liu Biao in order to resist Cao Cao, on the one hand, Liu Bei was collected as a northern barrier, on the other hand, he actively united the Yuan group in the north, and advised the Yuan brothers to negotiate peace.

On the other hand, Cao Cao was also preparing to help Zhang Xian and others go south to defeat Liu Biao many times, but was dissuaded by Xun Yu, Xun You and others, and finally turned to fight against the Yuan clan in the north wholeheartedly, using the opportunity of his internal fighting to pacify the north.

Cao Cao never gave up on taking Jingzhou, and after Sun Quan eliminated Huang Zu, he rushed south before Sun Quan, but by this time Liu Biao had already come to the end of his life.