The historical background of Li Su's entry into Cai on a snowy night.

Li Su attacked Cai Zhou on a snowy night and captured Wu Yuanji alive, which is a typical successful surprise attack.

In the 9th year of Yuanhe in Tang Xianzong (8 14), in August, Zhang Yijun (Huaixi) appointed Wu Shaoyang as our ambassador. His son Wu Yuanji concealed the news of Shaoyang's death and took over military affairs to support himself. The first town in Huaixi is only the land of Cai (now Runan, Henan), Shen (now Xinyang, Henan) and Guang (now Huangchuan, Henan). During the Tang Dynasty, it was surrounded by counties and isolated from the world. 10, Tang Xianzong, who has always been interested in pacifying the buffer region, made a decision to attack Huaixi and crusade against Wu Yuanji.

In the 10th year of Yuanhe (8 15), Wu Yuanji fought to the death under the siege of Tang Jun, and sent people to Chengde Wang Chengzong and Lizi Qingshi Island for help. On the one hand, Wang and Li asked for forgiveness of Wu Yuanji, on the other hand, they sent troops to coordinate Huaixi, sent people to burn the money, grain, silk and grass stored in the court, and assassinated the prime minister Wu, who urged the crusade. Xianzong was unmoved, and promoted Pei Du, who advocated fighting, as prime minister, and made him preside over the conquest, replacing Yan Yong, who had been fighting for a year and had no job, with Han Hong. At the same time, he accused Wang Chengzong of assassinating Wu and ordered an attack on Chengde.

In the 11th year of Yuanhe (8 16), Tang Jun invaded Germany. Due to the lack of supreme commander, it was difficult for the Tang army to coordinate their actions, and they were defeated by Wang Chengzong one by one. Tang Jun of Huaixi Theater had to fight alone because of the self-esteem of coach Han Hong. East Road Tang Jun defeated Huaixi Army and captured Gao (now Qiu Dong, Henan). North Road Tang Jun defeated Huaixi Army in succession. South Road, Tang Jun also breached the outer city of China. West Road Tang Army defeated Huaixi Army in Langshan (now Queshan, Henan Province) and was later defeated by Tiecheng (now southwest of Suiping, Henan Province). Both China and foreign countries were shocked. However, Xian Zong was determined to continue fighting, and took Li Su, the son of the famous Li Sheng, as the commander-in-chief of Tang Jun on the western front.

In the 12th year of Yuanhe (8 17), the war against Huaixi entered a crucial year. In May, Xianzong ordered to stop fighting against Chengde, determined to concentrate on pacifying Huaixi first. At this point, Li led the town of Tang Jun, Heyang, Xuanwu, Weibo, Hedong and Zhongwu on the North Road, crossed the Ganshui River, entered Yancheng, and defeated 30,000 soldiers in Huaixi and annihilated 23 out of 10. Yancheng ordered Dong Changling and Shoujiang Deng Huaijin to gather in the city and surrender to the Tang Dynasty. When Wu Yuanji learned that Yancheng was lost, he was terrified and transferred all the defenders of Cai Zhou to the northern line to reinforce Dong's heavy defense. The main force and elite of Huaixi Army were attracted to the northern line. This created conditions for the surprise attack of West Road Tang Jun on Cai Zhou.

In June of this year, Wu Yuanji saw that many of his men surrendered to the Tang Dynasty and their troops were weak, so he confessed on the table and claimed that he was willing to return to the DPRK. In the constitutional sect, envoys were given a letter, which allowed them to avoid capital punishment. However, Wu was held hostage by his left and right armies and generals and could not return to North Korea. Huaixi has reached the end of the road and the sun can set.

In July, Tang Xianzong, which fought in Huaixi for four years, was tired of traffic and people. He was deeply worried about this, so he appointed Pei Du, who had the strongest main battle strength, to lead our time and Huaixi Rebel Army, and advised him to bid on the front line.

In August, after Pei Du arrived in Yancheng, the above table said that all roads were supervised by eunuchs, and soldiers advanced and retreated by intervention. If you win, you will be rewarded by it, and if you lose, you will be humiliated by it. No one wants to go to great lengths. Xianzong allowed him to play and informed him to be an envoy in various prisons. The generals began to act arbitrarily and the war became more effective. Li Su was thus able to develop his talents without hindrance.

After Li Su arrived in Tang Zhou (now Biyang, Henan), he took various measures and actions, which laid the foundation for the success of the surprise attack.

First of all, as soon as he got off the bus, he went to see the soldiers in person to comfort the wounded and sick, so as to stabilize the morale of the army. At the same time, he deliberately showed weakness, pretended to be soft and lazy, and was lenient and lazy in the garrison to paralyze the enemy. Huaixi Army defeated Tang Jun repeatedly in West Road. Seeing that Li Su was in a humble position and behaved so badly, it took it lightly and stopped taking strict precautions against Tang Jun in West Road.

Secondly, in order to strengthen the military strength of the Western Front, implement and complete the surprise attack plan, Li Su asked the imperial court to gather 2,000 foot soldiers from Zhao Yi, Zhonghe and Yanfang.

Third, in order to win the hearts of the people in Huaixi and isolate and disintegrate Wu Yuanji, Li Su also took advantage of the years of war in Huaixi, the agricultural production was abandoned, and the granaries were empty. Many people had no chance of food and fled to the areas controlled by Tang Jun. They set up more than 5,000 households in Huaixi county, chose county orders for them, instructed them to raise them properly, and sent troops to protect them.

Thirdly, in order to shake and disintegrate the morale of Huaixi Army and strive for the use of Huaixi Army, Li Su also adopted the policy of giving preferential treatment to prisoners and boldly reusing surrenders. After he captured Ding Shiliang, the hero of Huaixi, he not only didn't kill him, but held an important position in the official residence. Ding Shiliang was so grateful that he offered a plan to capture Chen Guangqia, the mastermind of Wu Xiulin Department, at Wenchengzha (now southwest of Suiping, Henan Province) and recruited 3,000 people from Wu Xiulin Department. Tang Jun's morale in West Road is high, many cities are connected, and soldiers in Huaixi are in an endless stream. Li Su asked Cai Zhou for advice and Wu Xiulin for advice. Wu Xiulin thinks that only Li You can capture Cai Zhou alive. Li Su designed to capture Li You alive to avoid his death, and appointed him as the general of his dental team-the military envoy of the Sixth Hospital. Li You was moved by Li Su's cronies and reuse, and tried his best to make suggestions for the crusade against Cai Zhou. While giving preferential treatment to defected and captured Huaixi soldiers and their families, Li Su paid great attention to asking the inside story of Huaixi. He also abolished Huaixi's old order to hide spies and gave preferential treatment to arrested spies. As a result, the enemy spy told the truth, which was used by Li Su. In this way, Li Su quickly understood the enemy's fragility, distance and reality, and laid the foundation for avoiding reality and making an imaginary attack on Cai Zhou.

Finally, in order to sweep away the periphery, isolate Cai Zhou and establish a surprise attack base near Cai Zhou, Li Su successively sent troops to capture Wenchengzha, Maanshan, Lukouzha, Chayashan, Melting Furnace City and Xiping strongholds in the west and northwest of Cai Zhou, and joined forces with Tang Jun in the northern part of Yancheng. He also sent troops to conquer Baigou, Wengang and Zhucheng in the south and southwest of Cai Zhou, and cut off the connection between Cai Zhou and Shen Guang. The main force of Su Lijun entered Wenchengzha, which is only 65km away from Cai Zhou.

In September, Li You saw that the conditions for a sudden attack were ripe. He told Li Su that all the soldiers in Huaixi were in Qu Hui and the border, and all the people guarding Cai Zhou were old and weak. They can take advantage of their weaknesses, take advantage of them, take them by surprise, and capture Wu Yuanji in one fell swoop. Li Su was deeply moved and sent someone to secretly present the surprise attack plan to Pei Du. Pei Du was very grateful and agreed to send troops.

10/0, Li Su took advantage of the snowstorm, and the enemy relaxed their vigilance, which was conducive to unexpected weather. He ordered Shi Min to stay in Wencheng Town, with 3,000 trained death squads such as Li You as the vanguard, 3,000 of him and the prison army as Zhong Jun, and 3,000 of Li Jincheng as the rear. The action of the army is very secret. Except for a few generals, the whole army doesn't know the destination of the March and the task of the troops. Li Su only ordered to go east. After 30 kilometers eastbound, Tang Jun arrived at Zhangchai Village at night, and was caught off guard by the defenders, who wiped out all the defenders, including the soldiers who were in charge of vigilance. After the whole army had a rest, Li Su left 500 people guarding the city gate to guard against the enemy in the direction of Wolf Mountain, and another 500 people cut off the bridge leading to Qu Hui and ordered the whole army to March immediately. When the generals asked where the troops were going, Li Su announced that he would go to Cai Zhou and take Wu Yuanji directly. People were frightened to disgrace, but the military orders were like mountains, so they had to lead troops to the southeast.

At this time, the night was cold, the snow was blowing heavily, and the standard was broken. The people who froze to death looked at each other on the road. The road to the east end of Zhangchai Village was unknown to the Tang army, and everyone thought they would die, but everyone was afraid of Li Su, and no one dared to disobey orders.

In the middle of the night, it snowed harder and harder. Tang Jun marched 35 kilometers and finally arrived in Cai Zhou.

There is a chicken and duck pond near the city. Li Su ordered his foot soldiers to beat chickens and ducks to cover up the marching sound. Since Wu Shaocheng resisted the imperial edict, Tang Jun has not been to the gate of Cai Zhou for more than 30 years, so Caizhou people were unprepared and did not find Tang Jun's action. At four o'clock, Li Su's army arrived at the gates of Caizhou, and the people guarding the city didn't know it. Li You and Li Zhongyi dug a hole in the wall and took the lead in boarding the outer city gate, killing the sleeping gatekeeper, leaving only the night watchman to ring the bell as usual, so as not to disturb the enemy. Let's talk about Li Jue and others' success, so they opened the city gate to meet the enemy. Then, attack the inner city according to law. At dawn, the snow gradually stopped, and Li Su entered Wu Yuanji's outer house. At this time, someone noticed that the situation was different and told Wu Yuanji that the loyalist was coming. Wu Yuanji, still awake, smiled and replied, "The prisoners are in trouble. These guys should be killed at dawn." . Then it is reported that the city has fallen. Yuanji still casually said, this must be the children of Qu Hui defenders asking me for warm clothes. After getting up, Wu Yuanji heard Tang Jun's command, and nearly ten thousand people responded, only to have a fear, and he led the team to resist.

When Li Su entered the city, he sent someone to attack Yacheng, caressing Dong Chong's family and sending his son to give birth to him. Dong Chongdan surrendered in front of Su Lijun, and Wu Yuanji lost the hope of Qu Hui's defenders' Huiyuan.

On the 12th, Tang Jun attacked Yacheng again, and Caizhou people scrambled to help Tang Jun burn the south gate of Yacheng. At dusk, the city gate was broken and Wu Yuanji surrendered. More than 20,000 soldiers from towns such as Shen and Guang also successively descended to the Tang Dynasty, and Huaixi was pacified.

The success of Li Su's surprise attack was not accidental. Subjectively, Li Su managed the army well, kept his promise, treated the soldiers well, and won the hearts of scholars; Knowing people and being good at their duties, dare to reuse surrenders and get the enemy's situation; Seeing the possibility of breaking the game, he dared to seize Cai Zhou's space and carry out a surprise attack; He is also good at strategy, paralyzing the enemy and disintegrating his people's hearts and morale. All these enabled him to take advantage of the gloomy weather in which snow and fire were not connected, go deep alone, be completely annihilated, and win a surprise attack. Objectively speaking, Tang Xianzong and Pei Du never changed their determination to pacify Huaixi. Instead, they were able to concentrate on attacking Wu Yuanji, and even moved the envoys out of prison. The Bei Tang army contained and attracted the main forces of Huaixi, which created favorable conditions for the victory of the surprise attack.

After Huai Xiping's decision, all provinces were afraid and uneasy. Henghai made Cheng Quan an official in the DPRK on invitation, and the court recovered Cang and Jing (now northeast of Jingxian County, Hebei Province). Liu, general manager of Youzhou (now Beijing) Town, please submit. Chengde Town also made a new start on the table, offering Dede and Di (now southeast of Shandong Huimin) two states, and asking the court to appoint the following officials from other states. After Wang Chengzong died of illness, his brother Wang Chengyuan surrendered. The court also tried to pacify the prestige of Huaixi, strive for the peace of Zi and Shidao, and recover twelve states, such as Zi (now south of Zibo, Shandong Province) and Qing (now Qingzhou, Shandong Province). As a result, the separatist regime of the buffer region temporarily came to an end and the Tang Dynasty was reunified.