When Zhang Yi took Jia Siqian to conduct agricultural research, the north was once again in turmoil.

After Yuan Tan's defeat, the entire Yuan clan listened to Yuan Shang. Although the Yuan clan is in decline, there are still two states to use. Even if the Liaodong part of Youzhou is in the hands of Gongsun Du, the Yuan family also has a half-state, which can raise tens of thousands of troops at any time.

When Gao Gan, who had been a centrist before, received the news of Yuan Tan's defeat and death, he immediately sent the news to Yuan Shang and told Yuan Shang about the 50,000 he had prepared in Bingzhou. Yuan Shang was overjoyed after hearing this, and immediately asked Gao Gan to send troops from Bingzhou to recapture Jizhou.

Gao Gan is also very contradictory, he has ambition but no corresponding ability. He didn't have much loyalty to the Yuan clan, but he and the Yuan clan were already people on the same warship, and it was impossible to get off the ship.

Previously, Yuan Shang sent him and Guo Yuan and the Southern Xiongnu Shan Yu to attack Hedong, but he did not attack it himself, but handed it over to Guo Yuan. As a result, Guo Yuan was killed by Ma Tengjun invited by Zhong Xuan, and the Southern Xiongnu surrendered. Gao Gan shrank up in Bingzhou, and did not dare to send troops again.

Before Yuan Shang fled to Youzhou, he sent a recruit to Shangdang to transport grain. When Yuan Shang's army was defeated in Zhongshan, he thought that there was a big river in the east of Bingzhou, and there were 50,000 troops in Shanxi, which was easy to defend and difficult to attack, so he persuaded the senior cadre Yuan Shang to take Yuan Shang to Bingzhou to defend against Cao Cao.

Gao Gan was selfish, not only did he not agree with the idea of pulling the move, but he wanted to harm the trick, and forced the trick to take refuge in Cao Cao. Later, Gao Gan surrendered to Cao Cao, and Cao Cao, in order to win people's hearts, still appointed him as the assassin of the state. Last year, Cao Cao withdrew his troops in order to rescue Xiangyang, and the senior cadres asked the chief of the famous man for advice.

Zhong Changtong clearly told him, "You have the ambition to do great things but you don't have the ability to do great things, and you like to recruit scholars but are not good at selecting talents, this is what you have to be very vigilant about." ”

But Gao Gan thought very highly of himself, and did not listen to him, so he rebelled with the state. Cao Cao obviously expected this, and had already let Zhang He defend in Yecheng.

Gao Gan attacked Shangdang, captured the Taishou sent by Cao Cao to Shangdang, and took Huguan, where the garrison was located. He sent someone to contact Yuan Shang, and after receiving Yuan Shang's order, he immediately went out of Huguan. Guolu County attacked the country and attacked Yecheng.

But it's a pity that when he first arrived in the country, he was discovered by Xun Yan and immediately sent a military report to Zhang He. Zhang He received the military information and immediately rescued the country from Yecheng. Gao Gan was indeed ambitious and talented, and when he was attacking the city, he was attacked by Zhang He and returned defeated. There were only more than 30,000 of the 50,000 troops left, and Gao Gan returned to Huguan in a panic and guarded the pass.

Zhang He attacked Lu County and stopped in front of Huguan. His army was not large and could not attack Huguan at all, so he sent a letter to Xuchang asking for reinforcements.

At this time, it was almost a year since the first battle of Xiangyang, and Cao Cao had recovered this year. He was going to attack Youzhou this winter or next spring, but he didn't expect the high-ranking cadres of the state to move first. Since Zhang He defeated Gao Gan, it would be good to fight and merge with the state first.

Cao Cao immediately personally led his troops into Hanoi County. Hanoi County and Yingchuan County are next to each other, and it is only two or three hundred miles from Xuchang to Shangdang Gaodu County, the southernmost county of Bingzhou, which is closer than Yecheng. Cao Cao chose Lejin as the vanguard, crossed the Taihang Mountain from Huai County, and attacked Tianjing Pass. Gao Gan's attention was attracted by Zhang He of Huguan, and Le Jin easily laid down Tianjing Pass, and then captured Gaodu and Beishang Hyun County, and the soldiers pointed directly at the eldest son county of Shangdang County.

The people in the eldest son county were very dissatisfied with the high cadres and surrendered the city. Cao Cao stationed his eldest son, and let Le attack Tunliu County and threaten Huguan.

The high cadres of Huguan found that they were besieged, and immediately chose to retreat in a panic, retreating north to Tongba County, passing through Nie County, and returning to Taiyuan County.

Gao Gan had always been in Taiyuan County before, so he chose to flee north to Taiyuan County as soon as possible.

Cao Cao and Zhang He joined forces, followed Gao Gan into Taiyuan County, and stopped in Qi County. Cao Cao sent Zhang He and Le Jin to attack Jinyang.

Gao Gan had been in Taiyuan before, and many people were very dissatisfied, and some people surrendered along the way. So Cao Cao's army was overwhelmed, and directly attacked under the city of Jinyang, and most of Gao Gan's army dissipated when he fled back. Along the way, there were people who surrendered to Cao Cao, and there were only seven or eight thousand people left in the senior cadres, and none of these people were willing to give him their lives.

Le Jin commanded the siege and soon broke through Jinyang. Gao Gan had no choice but to flee from Jinyang again with his henchmen and flee westward.

The threat of Gao Gan had been cleared, and Cao Cao decided to return to Yecheng, leaving Lejin and Zhang He to clear and annex the state. After he returned to Yecheng, he immediately sent Zhang Yan of Montenegro to march into Bingzhou to help clean up the mountain bandits. The state was mountainous, and Zhang Yan had a lot of experience in mountain warfare, so Cao Cao sent him over.

Zhang Yan is known as a Montenegro thief, but this Montenegro does not specifically refer to a certain mountain, but a collective name for many mountains in Changshan, Zhaojun, Zhongshan, Shangdang, Hanoi and other counties. Zhang Yan's Black Mountain Army is the collective name of the bandits in these places, and it is their union. When Cao Cao captured Yecheng, Zhang Yan took refuge in Cao Cao and was named the general of Pingbei. However, at first, Cao Cao did not trust Zhang Yan very much, and asked him to lead troops to garrison Yecheng, which meant that Zhang He would spy on Zhang Yan.

After more than a year of observation, Cao Cao had a certain trust in Zhang Yan. This still has something to do with Zhang Xiu, Cao Cao's subordinates have many surrenderers who belong to one of the forces, but Zhang Xiu and Zhang Yan are the most special, because they were both princes before they surrendered. Zhang Xiu's previous performance was very good, and he also won a lot of impression points for Zhang Yan.

Zhang Yan entered Taiyuan County and attacked and merged with Le Jin and Zhang He. Le went in to pursue Gao Gan, Zhang He also attacked Xihe County to the west, and Zhang Yan went north to Yanmen County.

Gao Gan fled all the way west to the court of the Southern Xiongnu and sought refuge in Shan Yu Huchuquan of the Southern Xiongnu.

Ever since Hedong was defeated, Hu Chuquan had been afraid of Cao Cao. Although he had no loyalty to Cao Cao, he was afraid that Cao Cao would trouble him. So he rejected Gao Gan, and Gao Gan had no choice but to run away again.

This time, Gao Gan chose to flee like Jingzhou, his news was a little behind, and he thought that Jingzhou was Liu Biao's territory. Liu Biao and Yuan Shao had a relationship, and they had sent someone to persuade Cao Cao before, and wrote letters to Yuan Shang and Yuan Tan to dissuade the two brothers from fighting.

When it was time to arrive at Hedong County, it was just in time for Zhang Baiqi to attack Dongyuan County, and Yu Weigu and Zhang Sheng responded and confronted Hedong Taishou Duji. Gao Gan, Wei Gu and Zhang Sheng attacked Du Ji and were in a stalemate. At this time, Zhang Ji once again asked Ma Teng for help, and together with Zhong Xuan's soldiers and horses, defeated Gao Gan and others, and captured and killed Wei Gu and Zhang Sheng.

The Gao cadres were defeated and fled south again, but they were captured and killed by Wang Yan, the captain of Sili, and the head was sent to Xuchang for merit.