In addition, Gu Xijiu, deputy commander of the 36th Division, led the New 1st Brigade, the 1st, 2nd, and 3rd Independent Regiments, the 3rd and 6th Shaanxi Security Regiments, and the 1st Gansu Security Regiment as the Longdong Corps.

The reserve of the Sui Department was placed in the central part of Yijun with the main force of the 10th Division, Luochuan with the entire 76th Division (the 1st Brigade owed), the 48th Brigade near Yaoxian and Malan, the main force of the 1st Cavalry Brigade in Pingliang, and the 1st Brigade near Jingchuan.

From the point of view of road conditions, the local roads are scarce, only Luochuan to Yan'an has a poor road, barely able to pass cars, the rest of the roads are sheep's intestine paths, and the army is difficult to move. Especially in the northern part of Shaanxi, the terrain is more severe, the deep ditch is vertical and horizontal, the distance vision is like a flat land, there is often a deep ditch of dozens of zhang in the middle, although the opposite side can shout correspondingly, but it takes several hours to arrive, and the mule is difficult to get down immediately, the vehicle is even more impassable, and the traffic supply is inconvenient. Hu Zongnan focused his attack on the right flank, believing that he could achieve the effect of "taking the enemy by surprise," but in fact it only increased the difficulty of the troops' attack, so he was complained about afterwards.

In addition, the Kuomintang army did not have a 1/50,000 map of the Shaanxi-Gansu-Ningbo region at that time, and the operational command post relied on an extremely inaccurate 1/100,000 map drawn several years ago.

Beginning on 11 March, the Kuomintang Air Force began to conduct aerial reconnaissance of Yan'an, and carried out the first bombing in the afternoon of the same day after the personnel of the US military observation group withdrew from Yan'an. On the 12th, the Kuomintang troops on the northern and western fronts began to launch offensives. Around 13 March, Wang Shuming, deputy commander of the Kuomintang Air Force, rushed to Xi'an and mobilized 8 B-24 bombers and 23 squadrons of P-51 fighters to arrive at the airports of Juxian and Xi'an, together with the original planes, a total of 100 planes of various types. On the 13th, 94 sorties were dispatched to bomb Yan'an, and in the afternoon of the same day, one even exploded in front of the cave where Mao lived. It is really a big fuss to stir up the people in this way. At that time, Yan'an had neither air force nor air defense capabilities, and there were not many troops, and the Kuomintang army's approach had no military significance except for its political and psychological role. In particular, the Kuomintang military services did not yet have the ability to fight in a joint manner, and the coordination between the ground and air was poor. The Air Force requires that the information or requests sent by the Army reach the Air Force command post within two hours, but in practice, the transmission of information often takes more than 10 or even dozens of hours, and from the Air Force's point of view, it has completely lost its value and cannot be dispatched to cooperate. Therefore, the Air Force played very little role in the operations of the entire Northwest Theater except for aerial reconnaissance (because it was difficult for the Kuomintang army to obtain accurate information from the PLA, it had to rely on aerial reconnaissance).

Mao ** wanted to give up Yan'an, which was something that many soldiers and civilians in Yan'an couldn't figure out at that time, and it was emotionally unacceptable. At that time, Shi Zhe, director of the Office of the Secretariat of the CPC Central Committee, couldn't figure it out. He recalled: "One night after the Battle of Yan'an began, I rode a horse from Zaoyuan and rushed dozens of miles to Wangjiaping to meet Chairman Mao. "I asked worriedly what the chairman's preparations should do. Do you have to evacuate? Can you try to keep Yan'an without retreating?" The chairman lit a cigarette, turned around and smiled and opened the conversation: Your ideas are not high, not smart. They should not be prevented from entering and occupying Yan'an. Do you know? Chiang Kai-shek's Ah Q was full of spirit, and when he occupied Yan'an, he thought he was victorious. But in fact, as soon as he occupied Yan'an, he lost everything. First of all, the people of the whole country and even the whole world knew that it was Chiang Kai-shek who betrayed his promise, undermined peace, started a civil war, brought disaster to the country and the people, and was unpopular. This is the main aspect. However, Chairman Chiang also had his own ideas: as soon as he occupied Yan'an, he could announce to the whole country and the whole world that the headquarters of the Communist Party of the "** nest" had been destroyed, and now only bandits remained, and he was only suppressing bandits, so that he could block foreign interference. However, this is only Chairman Chiang's own thoughts, and it is his personal plan, not public opinion. But herein lies the characteristics of this person. He only thinks about himself, and he doesn't care what others are thinking or thinking. In addition, it should be known that since Yan'an is a world-famous city, it is also a heavy burden. Since he has to carry this burden, let him carry it. And then again, since you can fight to Yan'an, I can also call Nanjing. It's okay to come and not be rude. ”

The local villagers couldn't figure it out, and Mao ** patiently did their work in more popular language. "For example, a man who was carrying a heavy burden full of gold and silver treasures met a robber who was robbing the way and wanted to rob him. What should this person do? If he is reluctant to throw away his burden for a while, his hands and feet are very inadequate, and he will not win a battle with a robber, and if he is killed by a robber, his gold and silver treasures will be lost. On the other hand, if he throws away his burden and goes into battle lightly, he will be flexible and able to use his whole body martial arts to fight against the robbers, not only can he repel the robbers, but also may beat the robbers to death, and finally save the gold and silver treasures. When we temporarily abandon Yan'an, we are giving up the burden on the enemy's back, so that we can take the initiative and be more flexible in fighting, so that we can destroy the enemy in large numbers, and when the time comes, we will hold a counteroffensive again, and Yan'an will return to our hands. ”

Mao ** also encouraged the vast number of soldiers to say that when we fight, we do not win or lose in one city or pool, but in destroying the enemy's living forces. If people lose land, people and land will survive; If the land is lost, the people and the land are lost. The enemy entered Yan'an with a fist, and when he arrived in Yan'an, he had to stretch out his fingers, so that it would be convenient for us to cut them off one by one. We must tell our comrades that we will come back in one year or two years at most, and we will exchange one Yan'an for the whole of China.

On the evening of March 18, 1947, Mao ** calmly had dinner and evacuated Yan'an with Zhou Enlai. In the month and a half after taking the initiative to abandon Yan'an, the Northwest People's Liberated Area with less than 30,000 troops, in accordance with the "mushroom tactics" proposed by Mao **, the Kuomintang army, which was as many as 10 times larger than itself, calmly maneuvered, fought three battles and won three victories, wiped out more than 14,000 Kuomintang troops, dragged Hu Zongnan, Chiang Kai-shek's strategic reserve force, effectively responded to the People's Liberation Army in other battlefields, and laid the foundation for the victory of the Northwest Battlefield and the entire Liberation War, and truly realized what Mao ** said about exchanging one Yan'an for the whole of China.

On the morning of the 14th, the real offensive began, and the right corps of the Kuomintang Army took the entire 27th Division, the 29th Division, and the 1st Division as the first line, and advanced to the front line of Linzhen, Liucun, and Jiuzhicheng. By 18 o'clock on the same day, the Kuomintang army captured the line of the highlands north of Xigua Waist Hyeon, Yuejia Temple, and Biaojiatai. The original plan stipulated that on the first day, the entire 1st and 90th Divisions would occupy Jinpenwan, and the 27th Division would occupy Linzhen Town. The situation of the Kuomintang army on the left flank was slightly better, with the entire 17th Division and the entire 36th Division as the first line, attacking the line of Niuwu Town and Chafang, breaking through the right flank defense line of the 7th Police Regiment, and capturing Chafang at 13 o'clock in the afternoon and Dunxian County at 15 o'clock.

On the same day, Mao ** sent a telegram to Zhang Zongxun and *** saying that the enemy's deployment for attacking Yan'an was roughly divided into four routes, and asked Wang Zhen's troops to concentrate on Ganguyi from Yanshui Guanxi on the 15th, and assemble in Ganquan and north of Longitudinal Longitudinal Brigade, and the New Fourth Brigade to assemble in Yan'an.

On the 15th, the Kuomintang Right Corps continued to advance towards Jinpenwan and Linzhen Town, and with the support of the air force, at 17 o'clock on the same day, it entered the highlands of Jinpenwan and Linzhen Town, ten miles south of Linzhen Town, as well as the line of Dongjiatai and Santaizhuang, but still did not achieve the task of the first day. In the battle that day, it was still fighting against the forward detachments of the People's Liberation Army, and the outpost battalions of the main position on the front line of the teaching brigade had not yet moved. The left corps of the Kuomintang army attacked the line of Yulin Bridge and Beishan Temple on the same day, occupied Beishan Temple at 8 o'clock, and occupied Yulin Bridge at 17 o'clock.

On the 16th, the fighting became fiercer. Because of the slow progress a few days ago, Hu Zongnan was furious and asked Dong Zhao to take Yan'an within three days, otherwise the military law would be engaged. And announced which troops entered Yan'an first and would be rewarded with 10 million yuan. On the 16th, Mao issued an order to defend Yan'an, judging that "the enemy's casualties are very large, the difficulties have increased, and the fatigue will be even worse in the future", and asked all units to resist for another 10 days to two weeks (16 to 29 days) in the areas of Ganquan, Nanniwan, and Jinpenwan south of the Thirty Lipu and Songshuling lines, and ordered Zhang Zongxun and Liao Hansheng to command the One Brigade of the Right Wing Corps, the 358th Brigade, and the Seventh Police Regiment in a unified manner. organize defense in the area of the mountain temple; The Teaching Brigade and the Second Column were the left wing corps, under the command of Wang Zhen and Luo Yuanfa, and organized defenses in the Nanniwan, Jinpenwan, Linzhen, and Songshuling areas, requiring them to hold out for at least seven days; The New Fourth Brigade is the Central Corps, with no less than four battalions of troops, organizing defense in the Miaoerliang, Chengzigou, and Sanshilipu areas.

On the 17th, Hu Zongnan advanced to the line from Mazi Street to Jinpenwan in Ganquan County, and then changed his tactics and advanced cautiously. Peng Dehuai and *** immediately ordered the 1st Column and the newly formed 4th Brigade to join the battle. Taking advantage of the favorable terrain, the Northwest Field Force carried out active defense, organized counterattacks at an appropriate time, and flexibly attacked by taking advantage of the darkness of the night to harass and delay the offensive of the Kuomintang army. On the 18th, Hu Zongnan Group entered the first line of Twenty Lipu and Yangjiapan, 10 kilometers south of Yan'an; Ma Bufang and Ma Hongkui Group occupied Yanchi, Qingyang and other places; The 22nd Army launched an attack on Yokoyama. At this time, all organs and schools in Yan'an have been safely transferred, and the masses have been evacuated. That night, the Communist Party of China and the Central Committee led the central organs and the People's Liberation Army Headquarters to evacuate Yan'an. After six days and nights of fierce fighting, the Northwest Field Force annihilated more than 5,000 Kuomintang troops, completed the scheduled tasks, and also took the initiative to withdraw from Yan'an on the morning of the 19th. After that, Mao **, Zhou Enlai, secretary of the Secretariat of the CPC Central Committee and vice chairman of the Central Military Commission, and Ren Bishi, secretary of the Secretariat of the CPC Central Committee, continued to stay in northern Shaanxi and command the national liberation war.

On the same day, Mao ** signed an operational order to defend Yan'an in the name of the Central Military Commission, requiring the Northwest Field Corps to "concentrate more than five brigades to fight a mobile war after reaching fatigue and attrition of the enemy in defensive operations, annihilating the enemy individually, and completely smashing the enemy's attack." On March 18, 1947, before Mao ** and Zhou Enlai evacuated Yan'an, they met with Wang Zhen, who had just led his troops from Jinsui, and instructed Peng Dehuai to let the troops clean the house and yard. At dusk, Mao ** and Zhou Enlai reluctantly bid farewell to Yan'an, where they had lived for ten years, and embarked on a journey to northern Shaanxi.

By March 18, 1947, the transfer of the CCP's organs had been completed, and the Northwest Field Army took the initiative to withdraw from Yan'an on March 19, 1947.

After the Kuomintang army occupied Yan'an, it was constantly harassed and harassed by the Northwest Field Army, and the Kuomintang army was exhausted, grinding the enemy out of food. Taking advantage of this opportunity, the Northwest Field Army again concentrated its superior forces and waited for an opportunity to annihilate each one.

Due to the proper use of the tactics of the Yan'an Defense Campaign, the Kuomintang army suffered heavy losses, and even the slightest hair of the CCP's command center could not be touched。。。。。。。。。。。。。。。。。。。。。。。。