The Battle of Dingjunshan was an important battle in the Three Kingdoms era, Liu Bei sent the general Huang Zhong to attack Dingjun Mountain, Cao Cao personally led a large army to supervise the battle, Xiahou Yuan learned that Cao Cao personally came, adopted a firm strategy, and did not go to war, Cao Cao said that if he did not fight, it would be a sign of weakness, so he sent people to Dingjun Mountain with a festival, asked Xiahou Yuan to enter the army, and adopted an offensive posture.
At this time, a counselor named Liu Ye advised that General Xiahou Yuan's personality was too strong, and he was afraid that he would fall into the enemy's treacherous schemes. Cao Cao felt that it made sense, and after careful consideration, he wrote a handwritten letter and sent an emissary to Xiahou Yuan to warn Xiahou Yuan.

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Xiahou Yuan opened Cao Cao's handwriting and looked at it, only to see Cao Cao say a word, to the effect that all those who are generals should be strong and gentle, not just rely on the courage of flesh, if you only know how to fight brute force, a warrior can kill you, I am now leading a large army stationed in Nanzheng, to back you up, you are a wonderful talent, you must not insult these two words.
That is to say, Cao Cao warned Xiahou Yuan not to take the enemy lightly, not to only know how to fight and kill, the key is to rely on wisdom to win, and never overturn the ship in the gutter and humiliate yourself.
When Xiahou Yuan saw Cao Cao's letter, he was very happy, he was confident that he would be able to win this big war.
Xiahou Yuan was indeed a general, he was the person in charge of Cao Cao's military front in the west, he had swept away the Song Jianbu who had been rebelling in the west for more than thirty years, swept through Qiangxi, and hubu passed the right, and Cao Cao had to take Xiahou Yuan with him to meet those Qiangyuan leaders, because Xiahou Yuan could suppress those leaders, so it can be seen that Xiahou Yuan is very powerful.
However, just after Cao Cao's admonition, Xiahou Yuan was still careless and light on the enemy, and after a hundred battles in his life, he fought so many dangerous and vicious battles, all of which were safe and sound, but in the end, he still died in the battle at Dingjun Mountain, which became the place where Xiahou Yuan died.
At that time, Zhang Gao had dissuaded Xiahou Yuan not to take the enemy lightly and venture forward, but to stick to it, but Xiahou Yuan said that if he stuck to this place, how could he establish a meritorious deed? Only by taking the initiative to attack can I achieve battle achievements, if I insist on not fighting, others have achieved battle achievements, where is my face? What to take to see the King of Wei?
In this way, Xiahou Yuan adopted the strategy of taking the initiative to attack, marching into the challenge and pressing forward step by step, while Huang Zhong, under the staff of Fazheng, preemptively occupied a hill in Dingjun Shanxi, and then, taking advantage of the favorable terrain on the top of the mountain, to observe the enemy's situation at Dingjun Mountain. Xiahou Yuan learned that Huang Zhong occupied favorable terrain, so he led his troops to compete for favorable terrain.
Fa Zheng said to Huang Zhong, I am observing the enemy's movements on the mountain, no matter how Much Xiahou Yuan challenges and insults, do not go to battle, and when he is tired and relaxes his vigilance, when the general sees me raising the red flag, he will suddenly kill him, kill him by surprise, and the battle can be won.
Therefore, under the plot of Fazheng, Xiahou Yuan was indeed in the plan, and when there was no defense, Huang Zhong suddenly killed, and Xiahou Yuan did not have time to meet the battle, so he was cut into two pieces by Huang Zhong. Otherwise, it would be very difficult for Huang Zhong to defeat Xiahou Yuan, who was also a first-class fierce general and his martial arts were not low.
As soon as the main general Xiahou Yuan died, the Cao army was in chaos and could not form an army, so Huang Zhong took advantage of the situation to defeat Zhang Guo, Zhang Gao was also defeated, and the Dingjun Mountain was returned to the Shu army.
Xiahou Yuan's death in battle was like breaking Cao Cao's arm, Cao Cao learned the news, cried loudly, and was heartbroken, the overall strength of Cao Cao's army was also severely damaged, and most importantly, Cao Cao lost an outstanding military commander from then on.
For Liu Bei, he occupied Dingjun Mountain, greatly increased his military strength, and eventually drove out Cao Cao and captured Hanzhong, becoming the biggest winner.