If there was a good thing called satellite map in the Tang Dynasty, then the monarchs and ministers of the prosperous Tang Dynasty might have become more humble and cautious. The territory of the Tang Empire reached its maximum around the second year of the General Chapter (669). Since then, it has gradually shrunk, losing all the Persian Governor's Mansion west of Congling, the Kunxu Prefecture Governor's Mansion, Tiaozhi Governor's Mansion, The territory of Feng Dudu's Mansion, Xiu Xian Dudu's Mansion, Yuezhi Dudu's Mansion, Gumo Prefecture Dudu's Mansion, Dawan Dudu's Mansion, Anxi Prefecture, etc. covers millions of square kilometers. At the same time, the northern nomads who originally submitted to the Tang Empire also rebelled one after another and formed a powerful Turkic state that threatened the safety of the Tang Dynasty. The territory of the Turkic tribes separated from the Tang Dynasty alone was almost four million square kilometers. Nowadays, the Turks are in the north and the Tubo people are in the west. The two countries are secretly colluding, intending to completely cut off the Tang Dynasty's road to Longyou, and then carve up the vast and fertile Longyou Road together. If the Chinese version of later generations resembles a strong and powerful rooster, then the Tang Dynasty version in the 25th year of Kaiyuan looks like a rooster without its fat butt and back, only dragging a fluffy big tail through a narrow passage. chicken! The Hexi main road leading to Longyou Road is only more than 200 miles at its narrowest point. If not for the Qilian Mountains, Daxue Mountains, Guzangnan Mountains, Ganjun Mountains, Yanzhi Mountains, Heli Mountains and other mountains that formed a natural barrier between the north and the south in the Hexi Corridor, Datang might have lost control of the Hexi Corridor at this time, and even The entire Longyou Road was completely lost. The importance of the Hexi Corridor to the Tang Dynasty is self-evident. The responsibilities and pressures on the Hexi Jiedushi, who is responsible for guarding the Hexi Corridor, can be imagined. It was precisely because the Hexi Army had been at war with the Turks and Tubo people in the north and south for a long time that when His Majesty the Emperor of the Tang Dynasty decided to give the Tubo people some color. The first thing that came to mind was to give orders to Hexi Jiedushi Cui Xiyi. The status of the Longyou Jiedushi is also very important, but unlike the Hexi Jiedushi, he has to face Turkic wolves and Tibetan wolves at the same time. The Longyou Jiedushi was stuck on the choke point for the Tubo people to advance eastward. Behind the Longyou Jiedushi was the Guanzhong area, where the imperial capital Chang'an was located! It should be noted that the Longyou Road of the Tang Dynasty refers to the Xinjiang region in later generations plus the northeastern part of the Pamir Plateau and part of Kazakhstan, while the area under the jurisdiction of the Longyou Jiedushi of the Tang Dynasty is the southeastern part of Gansu Province in later generations. The part that borders Shaanxi Province. There is also a small part of the northeastern part of Qinghai Province. In later generations, Gansu Province looked like a slanted dumbbell or meat bone on the map. Its two ends were relatively fat, while the middle section was very long and narrow. This long and narrow section is what people have called the Hexi Corridor since the Qin and Han Dynasties. The area under the jurisdiction of Hexi Jiedushi Cui Xiyi is the middle section of the dumbbell, while the area under the jurisdiction of Longyou Jiedushi Wang Junkuo is the big hammer head under the dumbbell. The emperor ordered Cui Xiyi to command the troops in Hexi to launch a punitive war against the Tubo Kingdom. Because Cui Xiyi reached an agreement on peaceful coexistence with Kilixu a year ago, he did not want to do anything treacherous, so he brought Wang Junkuo in. In Cui Xiyi¡¯s view, Wang Junkuo would definitely have guessed his purpose, and maybe he was just perfunctory, cooperating with the Hexi Army to wave flags and cheers outside the field. They will not send out large armies to fight the Tubo people with real swords and guns. However, this time Cui Xiyi underestimated Wang Junkuo's determination and attitude. After receiving the secret report from Cui Xiyi, Lao Wang immediately summoned the governors of Longyou Prefecture to discuss the attack on Tubo, and the governor of Shanzhou Guo Yingyi was even more determined to support the war faction. After arranging tasks to various states, Wang Junkuo immediately wrote back to Cui Xiyi. Wang Junkuo teased Cui Xiyi in the letter and said: "Old Cui. This time you want to drag me to accompany you to be scolded. I don't blame you. I have already called on my brothers to prepare to beat up the Tibetan dogs. What are you preparing over there? How about it? If the Hexi Army doesn't move faster, I'm afraid it will just follow the Longyou Army and eat dust!" After Cui Xiyi received Wang Junkuo's secret message, he laughed and called Wang Junkuo an old dog, but he didn't do anything about it! Without hesitation, he immediately ordered the 30,000 troops from Hexi who were already prepared to advance southward from the Dadou Valley between the Daxue Mountains and the Qilian Mountains, and rushed into the territory of Tubo. At this time, in order to show his sincerity, Kilixu had withdrawn all the troops guarding the river on both sides of the Hemen River, leaving only some troops stationed at the northern end of Meng Valley and the Xincheng area. Therefore, when the East Route Army under the personal command of Cui Xiyi appeared north of Menggu, the Tubo garrison here was unprepared. After resisting in panic for a while, they fled southward from the Menggu Passage, preparing to go to Fuqi City to meet their commander. Kilizu's troops converged. The Tubo people had this kind of behavior. Taking advantage of their ability to move freely on horseback, whenever they felt that the Tang troops were too powerful to resist, they would run away. Wait until the chariots that cannot adapt to the plateau climate and the Tang army show off their powerAfter leaving, they will come back again. The Tubo people used this primitive guerrilla tactic to drag down the Tang Empire for more than a century. During these more than a hundred years, the Tubo country's national power not only did not weaken, but continued to grow. However, this time the Tibetan troops stationed at the northern end of Meng Valley made the wrong decision, because their retreat road to the south had been blocked in the Niuxindui area! Nan Jiyun and his 800 soldiers, who had been waiting patiently in the north of Niuxindui for nearly ten days, were now waiting for work, and each of them had adjusted their physical strength to the best condition. When they finally heard the dull sound of horse hooves coming from the depths of Meng Valley, there seemed to be bright piles of gold and silver waving towards them. The group of Tubo cavalry at the front were tasked with opening and exploring roads. They walked in this wide canyon more than once, so even on the road to escape, they were still not very vigilant. . However, when hundreds of Tibetan cavalry were about to rush out of Meng Valley, an earthen wall made of sacks appeared in their sight. The earthen wall is not high, about the level of a person's chest. You can cross it by urging your horse to jump forward suddenly. When the leader of the Tubo army looked at the Tang army behind the wall, he felt a little nervous, but his status as the leader of the Tubo scouts required him to make a quick decision at this time. The leader of the Tibetan scouts seemed to have heard the sound of the roaring army behind him, so he said to the soldiers around him in Tubo: "Let us rush over and kill all the ignorant Tang people in front of us!" The Tubo soldiers looked on. The hundreds of Tang troops behind the earthen wall also felt that the other side was overestimating their own capabilities and dared to block the southward retreat of their own army with just a few hundred soldiers, so they made chirping sounds together and waved their scimitars. , urging the war horse under his crotch to roar towards Nan Jiyun's position. "Myna, here we come, the Tubo people are coming!" A soldier who followed Nan Jiyun from Dunqiu to Shanzhou stood next to Nan Jiyun, muttering excitedly and nervously. "Shut your beak! I have eyes, and I have a clairvoyance in my hand, so I can see everything!" Nan Jiyun scolded this fellow villager in a low voice, and then began to mutter to himself: "Five hundred One step, four hundred and fifty steps, three hundred steps, the crossbowmen fired their arrows!" On both sides of the passage where the Tubo people rushed over, Nan Jiyun made a mark every fifty steps, which can be seen intuitively. Observed the distance between the Tibetan people and their own camp. The archers of the crossbow camp are equipped with two weapons: longbows and hand crossbows. Longbows are good for long-range shooting, but the rate of fire is low; hand crossbows are good for close combat. Although they are not as powerful as longbows, they are worse than longbows because they can fire continuously. For the first round of attacks on the Tubo people, the longbow is naturally the most suitable. Three hundred sharp arrows that had been strung up long ago roared and fired at the Tubo cavalry coming at high speed at the moment Nan Jiyun gave the order. The next moment, the Tibetan people who were hit by arrows on the opposite side let out shrill screams and fell to their horses one after another. Naturally, such concentrated fire could not kill all the Tibetan soldiers who were coming from behind. So after Nan Jiyun saw the first round of arrow rain passing, he immediately ordered the crossbowmen to put down their long bows and then raise their hands. Crossbow aims and shoots. After suffering heavy casualties, the Tubo cavalry finally approached within a hundred steps of the earth wall bunker. They also loaded their bows and arrows and began to fight back. "The crossbowmen lowered their heads and hid behind the bunker! The swordsmen and the ax shieldmen were ready for close combat!" The ground in front of the earth wall seemed to have no mechanism, but after the Tubo cavalry rushed in, they were all injured and died. The frightened horse fell off its back. There was that unlucky guy. When he landed, either his buttocks were pierced by caltrops, or his thighs and back were punctured. The pain suddenly became even more unbearable. There were hundreds of Tubo cavalry. Although 70% of them were damaged by this time, some scattered cavalry still insisted on rushing to the front of the earth wall. Nan Jiyun suddenly stood up from behind the bunker, and then shot the Tubo leader who was rushing at the front. "The Mo Dao camp attacks! The ax shield men cover!" The next moment, a bright forest of knives was drawn out from behind the earth wall, and they slashed hard at the four hooves and chest of the war horse the Tubo people were riding! The soldiers in Mo Dao Camp were all wearing heavy armor and steel helmets. When they practiced, they stood on the same spot and chopped the knife again and again. Now, the Tubo cavalry who appeared in front of them became the target of being hacked. The ax shield hand held a shield, stood beside the Mo Dao hand, and used the ax to cut off the necks of the Tubo people who fell into the bunker. His hands and feet were also very agile. From the time when hundreds of Turkic reconnaissance rangers started charging into the formation to the end of the battle,??It was actually very short, it probably only took dozens of blinks or dozens of breaths, but all the Tubo people who were still so aggressive fell into a pool of blood, and no one was spared or survived!