In ancient Chinese history, once the Central Plains Dynasty was in civil strife, the northern nomads would invade on a large scale and invade the border passes. The Three Kingdoms period was an exception, and although Cao Cao, Liu Bei, and Sun Quan fought each other, they had not heard that the Hu people in the north dared to take the opportunity to invade the Central Plains. Why?
It can be said that peace in the north was fought by Cao Cao. The northern nomads were not without covetousness for the Central Plains, but Cao Cao's army was a great wall in front of them, insurmountable. Someone once challenged this "Great Wall", it is Wuhuan, and the result is a fiasco at the Battle of White Wolf Mountain.
If the opponent of the Tang Dynasty was turkic and the opponent of the Han Dynasty was the Xiongnu, then the opponent of Cao Wei of the Three Kingdoms was Wuhuan. Wuhuan is a branch of the northern nomadic people, who were originally a small, unknown tribe on the grasslands, and did not rise rapidly until the end of the Eastern Han Dynasty.
At the end of the Eastern Han Dynasty, the Yellow Turban Rebellion broke out, the Central Plains Dynasty was overwhelmed, and the garrison of the border pass became more and more relaxed, and Wuhuan took this opportunity to develop and grow, forming the "Three Counties Wuhuan" centered on Liucheng, and the Western Liaoning region of the Han Empire became Wuhuan's sphere of influence. He was the most powerful tribal leader among them, and he was bent on emulating the Huns and dominating the north.
During his reign, Gongsun Zhan had been fighting against Wuhuan and successfully defended Youzhou and other places. However, in order to destroy Gongsun Zhan, Yuan Shao did not hesitate to ally with WuHuan. Gongsun Zhan defeated and set himself on fire, Yuan Shao occupied Youzhou, and in order to fulfill his promise, Yuan Shao made the leader of Wuhuan shan yu in the name of Emperor Xian of Han and engaged in a political marriage with Wuhuan.
This was the conflict between Cao Cao and Wu Huan, who was both a political and military alliance with the Yuan family, and although Yuan Shao died after the Battle of Guandu, Wu Huan continued to support yuan. Of course, Wu Huan's "never leave and never abandon" is not out of affection, and the purpose of taking in the remnants of the Yuan clan is to pull the banner of the Yuan clan, on the one hand, to establish hegemony in the Wuhuan tribe, and on the other hand, to win over the Han forces close to the Yuan clan. After receiving the remnants of Yuan's forces, he ruled a population of more than 300,000 people, more than tens of thousands of cavalry under his command, and his strength was strong.
Although Yuan Shao had been overthrown, Wu Huan repeatedly attacked the border passes under the guise of the Yuan clan, plundered the people, and abducted more than 100,000 households of the people of Youzhou. In the long run, Cao Cao's rule in Youzhou will cease to exist, and the already dying Yuan clan will also be revived with the support of Wu Huan.
Cao Cao certainly could not allow such a thing to happen, so he was determined to go on an expedition to Wuhuan Ton, completely eliminate the remnants of the Yuan clan, and remove obstacles to the unification of the north.
Cao Cao was a pragmatic faction, and he had already built two Caoyun in the eleventh year of Jian'an, in order to facilitate the transportation of grain to the north and prepare for the Northern Expedition.
However, among Cao Cao's generals, there was a great deal of disagreement about whether to go north.
"Yuan Shang is dead, Yi Di is greedy and has no relatives, how can he still use it!" Now that he is going deep into the expedition, Liu Bei will say that Liu Biao will attack Xu, and if something changes, there will be no regrets. (Zizhi Tongjian)
This was the unanimous view of most people, who feared that once the Northern Expedition, Liu Bei would encourage Liu Biao to attack Xu Du and sneak into the rear of Cao Jun.
But Guo Jia had a different view, and he made a judgment on the development of the current situation:
"Although the public is mighty and mighty, it will not be equipped, because it is unprepared, and if it strikes, it can be destroyed." And Yuan Shao had grace to Minyi, while the Shang brothers survived. The people of the present four states, in vain, with the power of the people, the deshi weijia, the southern expedition, the capital of the Wuhuan, the subject of the lord of death, the Hu people move, the people are all responsive, with the heart of life, into the plan of kai, fear of youth, hope for not their own. The table sits and talks about the guest's ears, self-knowledge is not enough to prepare, the heavy responsibility is afraid that it cannot be controlled, and the light task is not useful, although the virtual country is on an expedition, the public is worry-free. (Zizhi Tongjian)
Sitting back and watching Wuhuan become strong, the Yuan clan will make a comeback, and the northern states will be lost sooner or later, and Wuhuan will become a major problem for Cao Cao to chase the deer in the Central Plains; Liu Biao does not trust Liu Bei, and will not and does not dare to send troops to attack Xu Du. It is better to take advantage of the fact that Wuhuan is not ready to launch a surprise attack and settle it once and for all.
Judging from the results, Guo Jia's view was completely correct, but for Cao Cao at that time, this was undoubtedly a huge adventure.
Cao Cao was not afraid of taking risks, and he was determined to launch a northern expedition according to Guo Jia's strategy.
Unfortunately, the sky did not go according to people's wishes, just when Cao Cao was mobilizing soldiers and horses, grain and grass, heavy rain fell in the north, continuously, the roads were blocked, and it was difficult for the army to march. As a result, Wu Huan made preparations for war, and the Cao army had lost the opportunity to raid.
The raid failed, and all the generals advised Cao Cao to withdraw.
At the critical moment, it was Guo Jia who stood up again, and he suggested that Cao Cao's soldiers be fast, abandon heavy equipment, lightly loaded, and raid Wuhuan. At this time, Cao Cao was also guided by Tian Yu and learned of a secret road that had been abandoned.
This road is not even known to Wu Huan, but it is extremely dangerous. Cao's army was to climb over Mount Xuwu, exit the Chinese border, and pass through xianbei territory.
This kind of decision is like the Meridian Valley conspiracy, high risk and high reward, faced with the choice, Cao Cao once again chose to take risks, which also allowed him to create one of the most brilliant achievements in his military career.
After a rapid march, Cao Cao, Guo Jia, Zhang Liao, and others led the forward army to the vicinity of the White Wolf Mountain, which was less than 200 miles away from Liucheng. At this time, the Cao army had already encircled the rear road of Jiandun, but at the same time, their lightly armored army had no way back, and once defeated, Cao Cao and others would have no way to retreat.
It can be said that Cao Cao has already put all his wealth on the stake, the army is short and short, and the only thing left is a death battle. At this point, Cao Cao no longer interfered, and he gave all the command of the front to Zhang Liao.
Before this battle, Zhang Liao was not the number one person in Cao's army, but when everyone else advised Cao Cao to withdraw, Zhang Liao took the initiative to ask for battle.
Zhang Liao led the elite cavalry of Cao's army, including Cao Cao's proud tiger and leopard horse, and fought a bloody battle with tens of thousands of Wuhuan cavalry gathered in a hurry at the narrow White Wolf Mountain.
The number of Cao's army was not as strong as that of Wuhuan, but Zhang Liao charged fiercely, Cao Cao's tiger and leopard riding strength was strong, and The Wuhuan cavalry was out of various tribes, and there was no cohesion like Cao's army, when their formation shook slightly, the whole army fell into collapse. Zhang Liao took the lead, slashing at Shan Yu, and the Wuhuan army was leaderless, and finally suffered a fiasco.
After this battle, Cao Cao captured more than 200,000 people and collected Wu Huan's elite cavalry, which gave him the most powerful cavalry army in the Three Kingdoms. Cao Cao's unification of the entire north was also removed. Zhang Liao became famous in one battle and shocked the world. To Cao Cao's heartache, due to the cold and dry weather, Guo Jia, who was already weak, became ill on the march and died soon after.
Resources:
Zizhi Tongjian