Liu Yin did not finish writing the first draft of this article "Dingbeiping Lu Ce" until the lamp was lighted. He sprinkled tens of thousands of words, saying everything he thought was full of words, including many of which were written to express his thoughts. However, after rereading it, he still felt that there was something unsatisfactory, so he returned to his residence and deleted, edited and added it again, and did not stop writing until midnight.

‘Bang, bang, bang…’ Suddenly, a burst of firearm shooting sounded from afar, and the sound gradually became denser and could not be distinguished, as if there were wars around.

The old wife was frightened and put on her clothes. She pushed the window and looked out. She saw that the camp was as calm as usual. Under the lights, soldiers could be seen patrolling the building. There were also people on duty on the building. Liu Yin remembered the news that the Superintendent Zheng was rewarded by Bai Ri. He knew that the Song army was encircling and attacking the camp, but he also thought that there might be assassins infiltrated, so he hurriedly called his wife to close the window and close the door, and blow out the candlelight, so as not to cause trouble.

The couple was no longer sleepy. Liu Yin and his wife depended on each other to comfort him not to panic. This was the seat of the emperor of the Southern Dynasty, with elite alerts and large troops stationed around him. Even if there were tens of thousands of people attacking, they could not be easily captured. However, the sparse and dense gunfire outside and the footsteps of the soldiers dispatched in the camp still made the old wife uneasy.

Liu Yin looked at the flashes of the light and dark explosions that penetrated out of the window, and the gunshots from far to near, and knew that the battle was very fierce. He also knew in his heart that whether it was the disadvantaged Mongolian Yuan fighting for trapped beasts or the rapid advancement of the Southern Dynasty, they were eyeing the Central Plains, especially the battle for the Sixteen Prefectures of Youyun, because this place was too important for both the north and the south.

Military terms, the Sixteen Prefectures of Youyun are more than a thousand miles long from east to west. The northern part of the territory is the Yanshan Mountains and Taihang Mountains, which just "separates" the Central Plains agricultural areas from the northern nomadic areas. It is the natural dividing line between the Central Plains dynasties and northern tribes in history, and it is also the "golden channel" for the northern regimes to go south to the Central Plains.

The mountains in the northern part of Youzhou are the natural barriers for the Central Plains dynasty to fight against the northern nomadic cavalry to the south. Moreover, the western part of the Sixteen Prefectures of Yanyun is located in the northwest of Shanxi. There are many mountains and complex terrain, which is also not conducive to cavalry marching. In the central and southern areas of Yanyun, there are two rivers, Sanggan River and Juma River, which are the best natural barriers.

In addition to these natural dangers, the Central Plains dynasties have built a set of artificial defenses, including the Great Wall, Jinpo Pass, Juyong Pass, Gubeikou, Songting Pass, and Yu Pass. They are connected to mountains and rivers and become a complete defense system. Therefore, it is precisely because of these characteristics that there is a saying that "the states of Yan are built in heaven and earth, and they are divided into vassals. The limits of the Han Dynasty are that one man should be the pass, and ten thousand men cannot open it."

Therefore, if the cavalry of the nomadic people in the north want to attack the North China Plain, they must attack directly, or implement a large roundabout strategy and take a detour. It is extremely difficult for the army to cross these two mountains; for the other Central Plains dynasty, they can use mountains and rivers as obstacles to build a defense system, and only a small number of troops can defend. When war breaks out, the rivers are used for material transportation.

It is not difficult to see that the Sixteen Prefectures of Youyun are very important to all Central Plains dynasties. This place was once a key place for the Western Han Dynasty to fight against the Huns to the south, and it was equipped with cities such as Youbeiping and Pingcheng. During the Tang Dynasty, the position of Youzhou Grand Commander was established, and this place was built into a strategic location in the north. During the prosperous Tang Dynasty, An Lushan, who owned the Sixteen Prefectures of Youyun, used this place as a springboard to whistle south, almost losing half of the life of the Tang Dynasty.

Equally important, there are the economic conditions of the Sixteen Prefectures of Youyun. The environment here is warm and humid. The North China Plain is the three major plains in China. Its terrain is flat and open, and it is an important grain-producing land. Not only is the economy developed, but it also has a large population. Especially under the rule of the Liao Kingdom, it is "half of the tax region" and contributes a large amount of taxes every year, which is equivalent to giving the Liao Kingdom a great replenishment.

The significance of this matter is not just a question of how much more money is charged. Before the Song Dynasty, the biggest difficulty of the northern nomadic people was their backward economy and their inability to support long-term wars. However, the Liao Kingdom firmly grasped the Sixteen Prefectures of Youyun, and this shortcoming was filled in at once. On the contrary, with the developed agricultural handicraft industry, the potential for war is more than wings.

During the 25-year war with the Liao Kingdom in the early years of the Northern Song Dynasty, many battles of more than 10,000 people broke out between the two sides. The Liao Kingdom also suffered multiple casualties of more than 10,000 casualties and a large amount of material losses, but it was able to hold on and had the ability to launch a large-scale offensive against the Northern Song Dynasty, precisely because of the continuous replenishment of blood in the Land of the Clouds.

For the Song Dynasty, without the Sixteen Prefectures of Youyun, it was not just a problem of losing the barrier. It was simply a skylight: the Northern Song Dynasty established its capital in Bianjing, and there was no danger to guard around it, and it was all a plain. The Liao Kingdom, which had the advantage of cavalry, could go south at will later. "Want or not" and "how to fight" were completely in the hands of others, and it was simply a full and passive acceptance.

Now that the Mongol Yuan lost Dadu, it not only lost a prosperous capital, but actually lost its last foothold in the Central Plains and the path to a prosperous heaven. The Song Dynasty was frustrated for more than 300 years and was on the verge of destruction of the country twice. The root cause was also because it lost the barrier of Youyun, so of course it was inevitable for Dadu. It is not surprising that the two sides fought for the death...

The sound of gunfire around the camp gradually stopped before dawn, and after dawn Liu Yin opened the door to observe the situation. As soon as he walked out of his apartment, he saw several corpses lined up in the open space in the front yard of the inn, and the postmaster and the local people were identifying their identities. He leaned forward and took a look. Those people were all dressed in the Jianghu people, and they could not tell whether they were Han or Mongolians. The fatal injuries on their bodies were not caused by firearms, either shot into the vital points by crossbow arrows or stabbed into the vital points by swords.

Liu Yin asked his familiar postmen, and he probably didn't know that the guards belonging to the Imperial City Division were cleaning up the Mongols' light cavalry that had sneaked into the rear. He only said that the personal army of the guard camp searched for enemy spies and fought. An enemy assassin sneaked in under the guidance of the secret spy, trying to assassinate His Majesty and the ministers of the escort, but was discovered and killed by the guards.

Now after identification, one of them was the postman in the past. He was familiar with the layout of the postman, and it was his guidance that made the assassin sneak into the camp from the secret passage. The local clerk also recognized that one of the assassins was the "house" who was the "house" who was in charge of the household. Because he had no bad record, he had not been liquidated and had never shown any skills on weekdays. Unexpectedly, he was an archer who could shoot incense at night.

No one recognized the other assassins, but after inspection, they had calluses on their hands and had thick fingers. They should be people in the army who often shoot arrows with knives. In addition, they carried two stone bows and equipped with eagle feather arrows, they judged that they should be the great Khan of the Yuan Dynasty, the envoy, because eagle feather arrows were extremely rare and could not be possessed by ordinary military generals.

Although several assassins successfully avoided the post and sneaked into the camp, they were discovered by the lurking secret whistle. They were silently killed without getting close to the emperor's bedroom, and they did not even alarm His Majesty and his concubines. Liu Yin did not hear any movement in the camp. He could imagine that there were experts in secret guarding the emperor of the Southern Dynasty. When he first entered the camp, he wanted to find an opportunity to die with him. But now he thought that it was a joke, but I was afraid that he would be killed just now.

After breakfast, more news came out. Last night, Supervisor Zheng commanded the guards to launch a suppression of the elite enemy troops that infiltrated. The enemy hid in a vast manor of Otu merchants outside the city. When they went out in the dark night, the guards launched a raid. Both sides were elite soldiers, and the battle was naturally very fierce.

After a brief fierce battle, the guards of the Song army gained the upper hand. The remaining enemies hid in the manor, and were then attacked by the Song army, and then started to clear the village gate. The soldiers from bandits were very cruel and ignited the houses of the manor in an unknown situation. Anyone who escaped from it, regardless of age, was killed, regardless of soldiers and civilians, and did not accept surrender at all.

It is said that in the entire manor, in addition to the more than a hundred people in the family of the Otuo merchants, there were still thousands of servants and farmers. In addition, there were no less than three thousand Mongol Yuan soldiers who were avoided. They were all killed overnight and then put into fire and turned into ashes. It can be said that they were killed without leaving any leaves. The huge manor was burned to flat ground, and then they were arrested. The resisters were wiped out and no less than a thousand people were implicated.

After the assassins who had been infiltrated around the camp, they heard the sound of gunfire outside the city and knew that the situation had changed and the plan had been leaked. However, they had no way out and could only take a risk. If they succeeded by chance, they could still leave their families with their families, but the entire army was destroyed.

Later, Liu Yin discovered that there were Song army commuters coming in and out, and the Southern Emperor also urgently summoned his followers to discuss matters. He also learned from the words of others that it was not just this place that fierce battle last night. Instead, the Yuan army launched an attack on the Song army on more battle lines, using more than 10,000 troops. The battle was very fierce. The current battle was still ongoing, but it was difficult to make an accurate judgment on the intentions of the Mongolian Yuan for a while.

As time went by, more and more battle reports were reported everywhere, and the information was more and more detailed. The Yuan army's attacks included Tanzhou in the northeast, Liangxiang in the southwest, and Shunzhou in the southeast, and only the direction of Juyongguan was calm.

At first, everyone thought that the Yuan army launched an attack to cooperate with the raid on Zhuozhou and to restrain the Song army everywhere, so that they did not dare to send troops to reinforce the camp without authorization. However, no matter the success or failure of the plan to raid on Zhuozhou, anyone with a discerning eye could see that the result should be achieved after a night. According to this, the Yuan army should end the battle at dawn, rather than fighting for a long time without retreating.
Chapter completed!