At the end of the Eastern Han Dynasty, the masses were divided, and when the masses competed to dominate the Central Plains, Liaodong ushered in a period of relative tranquility, so under the governance of the Gongsun clan, Liaodong gradually became stronger. The Gongsun clan maneuvered between the state of Wei and the state of Wu, constantly expanding their own strength, they rectified the internal rule, developed the economy, conquered Goguryeo and Wuhuan, and then formed a powerful "kingdom", and later Gongsun Yuan, the descendant of the Gongsun clan, established the state of Yan, and declared himself a vassal to Eastern Wu as a foreign aid, but this angered Cao Wei, and the Wei Ming Emperor Cao Rui sent Sima Yi to lead an army to conquer the Yan state, which set off a huge battle, known in history as the "Battle of Annihilation of Yan".
Background to the war
At that time, Gongsun Du was appointed by Dong Zhuo as the Taishou of Liaodong, so Gongsun Du seized the opportunity of the masses competing to dominate the Central Plains to develop Liaodong, he reformed internally, rectified the administration of officials, developed the economy, and externally conquered Goguryeo and Wuhuan, so that the strength gradually grew, and in the heyday, it reached the central part of the Korean Peninsula in the east, crossed the Eastern Lai counties of the Shandong Peninsula in the south, reached the Luan River Valley in the west, and reached the Xianbei and Fuyu in the north, establishing a powerful local separatist regime in the northeast region. Later, Gongsun Du died, passed the position to Gongsun Kang, Gongsun Kang continued to govern the jurisdiction on the basis of Gongsun Du, which further enhanced the strength, after Gongsun Kang died of illness, because his children were still young, so he passed the position to his brother Gongsun Gong, Gongsun Gong then governed the jurisdiction, and constantly improved the order of the jurisdiction, but then Gongsun Gong gradually became a wasted person because of illness, and could no longer govern Liaodong, at this time Gongsun Kang's son Gongsun Yuan had grown up and was very angry in the face of his sick uncle. So forced his uncle Gongsun Gong to abdicate, he became the Taishou of Liaodong, Gongsun Yuan took office between Wei and Wu, and constantly expanded his strength, in the face of Cao Wei's pressing, Gongsun Yuan chose to claim the title of vassal to Eastern Wu, and hoped to get the assistance of Eastern Wu in the future, but the courtiers of Eastern Wu opposed Gongsun Yuan, believing that Gongsun Yuan would be defeated sooner or later, so do not aid Gongsun Yuan, but Sun Quan did not listen to the advice of the courtiers, so he sent envoys to Liaodong, carrying gold and jade jewelry, and established Gongsun Yuan as the King of Yan, Gongsun Yuan was flattered. However, thinking about it carefully, Cao Wei was close to him, and Eastern Wu was far away from him, which was not a long-term solution, so he killed the envoys of Eastern Wu and dedicated the heads of the envoys of Eastern Wu to the Wei Ming Emperor Cao Rui, who was very happy, so he appointed Gongsun Yuan as the Grand Sima and the Duke of Lelang, and let him continue to govern Liaodong, but as time went on, Gongsun Yuan's wings became more and more complete, so he became dissident, and repeatedly insulted the guests sent by Emperor Wei Ming to Liaodong, causing these guests to say bad things about Gongsun Yuan after they returned, and at this time Cao Rui wanted to appease Gongsun Yuan. So you can only endure. In 237 AD, Cao Rui sent Youzhou assassin Shi Yiqiu Jian to recruit Gongsun Yuan with a letter seal, Gongsun Yuan heard the news, immediately sent troops to block Yuqiu Jian, and launched a fierce battle with him, Yuqiu Jian saw that the situation was unfavorable to him, so he withdrew his troops, and went back to inform Emperor Wei Ming, Emperor Wei Ming still endured Gongsun Yuan, and soon after, Gongsun Yuan established himself as the King of Yan, established the State of Yan, and established a hundred officials, in order to consolidate his rule, so he once again declared himself a vassal to Eastern Wu, hoping to get the support of Eastern Wu, but this angered Cao Wei. Cao Wei then sent Sima Yi to lead an army to conquer Liaodong.
Ask before the war
Before the army went out, Emperor Wei Ming discussed countermeasures with Sima Yi, so Emperor Wei Ming said to Sima Yi, "What countermeasures does Gongsun Yuan have this time?" So Sima Yi replied: "Abandoning the city in advance and fleeing is the upper plan, relying on Liaoshui to resist our army, it is the middle plan, sitting on Xiangping, it is the next plan" Emperor Wei Ming asked: "What strategy will Gongsun Yuan adopt?" Sima Yi replied, "With Gongsun Yuan's wisdom, he will choose the middle plan and the lower plan, and he will use Liaoshui to resist our army, and then retreat to Xiangping." Emperor Wei Ming asked again, "How long does it take to go back and forth?" Sima Yi replied, "It takes a hundred days to reach Liaodong, a hundred days to return, another 100 days to attack, and another sixty days to rest, one year is enough." Subsequently, Sima Yi led an army to march.
The course of engagement
Sima Yi then led a 40,000-strong army from the Beijing Division to march to Liaodong, at the same time Xianbei, Goguryeo and other troops also sent troops to help, the Wei army was huge, vowing to flatten Liaodong, in June, Sima Yi led the army to Liaoshui, Gongsun Yuan heard the news, so he sent the generals Beiyan, Yang Zuo and others to lead the army to fight, they surrounded the Liaoshui for more than 20 miles, and built a high wall to block the Wei army, Sima Yi analyzed the battlefield situation at that time, so he decided to use the strategy of attacking the enemy with a plan, he adopted the strategy of attacking the west with sound, on the one hand, he pretended to attack the siege and strengthen the momentum. Attracting the enemy's main force, on the other hand, he led the army to quietly cross the Liaoshui River and forced into the enemy's Xiangping base camp, the general did not understand the reason, so he asked Sima Yi why, Sima Yi then said: "The enemy can't hold out, that is, he wants to exhaust us, let our soldiers run out of food, if we attack the city, we will be caught in the enemy's treacherous plan, now we go directly to their old nest, the enemy will definitely come back to the rescue, we can take the opportunity to break the enemy", so let the Wei army continue to move forward, straight to Xiangping, the enemy army heard the news and came out to intercept, Sima Yi saw that the enemy was in the middle of the plan, so he ordered a fierce attack on the enemy army, and launched a fierce battle with the enemy army, fighting three battles, all three battles were won, and the Wei army took advantage of the victory to besiege Xiangping City.
Siege and destruction of the city
At this time, Gongsun Yuan fell into a predicament, so he asked for help from Eastern Wu, so Sun Quan wrote to Gongsun Yuan, saying: "Sima Yi has always used soldiers, and he was deeply worried about his brother Xian", Gongsun Yuan saw that Eastern Wu had no intention of saving himself, so he could only lead his soldiers to defend Xiangping City, it was the rainy season, liaoshui was rising, which was somewhat unfavorable to the Wei army, and there were generals at that time who hoped that Sima Yi could move the camp, and sima Yi was furious, so he ordered the general to be killed and calmed the army.' At this time, Sima Yi knew that if the siege continued, the grain and grass in Xiangping City would be cut off, and sooner or later it would be conquered, so he patiently waited for the rain to stop, at this time some people in the court felt that Sima Yi deliberately delayed time, so they wanted Emperor Wei Ming to recall Sima Yi, but Emperor Wei Ming said: "Sima Yi is on the move, and the capture of Gongsun Yuan is just around the corner", so he continued to let Sima Yi stay at the front. Soon, the rain stopped, sima Yi's opportunity came, so Sima Yi ordered his soldiers to pile up mounds around Xiangping City, build watchtowers, and prepare a large number of stones, and use crossbows to fire at the city, at this time, the grain in Xiangping City was cut off, there was a tragic situation of people eating people, many people died, and some generals immediately surrendered to Cao Wei, of which Yang Zuo was among them. Sima Yi knew that the enemy army could not hold on, so he continued to attack the city, one night in August, a large meteor about ten meters long fell into Xiangping City, which caused panic among many people, Gongsun Yuan was also very afraid, so he asked King Xiang jian, Yushi Dafu Liu Fu asked Sima Yi to break the siege, but Sima Yi ordered the beheading of the envoy, Gongsun Yuan then continued to send people to ask for a break from the siege, but Sima Yi said to the envoy: "Either surrender or die", Gongsun Yuan then refused to tie himself up and plead guilty, and then led hundreds of horses to break through the siege from the southeast. Sima Yi then sent an army to pursue and kill Gongsun Yuan's troops, and killed Gongsun Yuan's father and son where the meteor fell, after attacking Xiangping City, Sima Yi slaughtered the city, killing all the men over the age of 15 in the city, about 7,000 people, and collected corpses, piled them up for everyone to see, and drove Gongsun Yuan's ministers to extinction, and killed more than 2,000 people, in order to deter the Liaodong soldiers and civilians, and the Liaodong soldiers and civilians immediately gave up resistance.
brief summary
In this way, Sima Yi led a large army to attack the city of Xiangping and destroy Gongsun Yuan, and all the counties in Liaodong were immediately pacified, and the State of Yan was completely destroyed.
References :Romance of the Three Kingdoms,Book of Jin