Just as Zhang Xuan led his army to expedition to Goguryeo, the Tang army also stepped up the battle on the Western Front. Xue Ju, Li Gui, Liang Shidu, and Liu Wuzhou were like four sharp daggers pressing against the back of the Tang Dynasty, making Li Yuan feel like a thorn in his throat and a thorn in his back. It is precisely for this reason that after the Tang army failed to attack Huguan, they immediately withdrew their troops back to Taiyuan. They no longer struggled with the attack on Huxu Hebei, but turned around to deal with Liu Wuzhou's southern invasion.

The Tang army had almost all 200,000 troops dealing with these four separatist forces, among which Liu Wuzhou was dealing with Li Yuanji, Li Gui was dealing with Li Jiancheng, and Xue Ju and Liang Shidu were led by Li Shimin to wipe out the 100,000 troops respectively.

The Tang Dynasty devoted all its strength to deal with these four forces and did make great progress within half a year. Li Jiancheng secretly sent the Wuwei tyrant An Xinggui to pretend to surrender to Li Gui, and persuaded his brother An Xiuren to surrender to the Tang Dynasty. The An brothers secretly colluded with the Hu people in Hexi to rebel against Li Gui. Taking advantage of Li Gui's army to lead his army to fight against the Qiang people in the west, he persuaded Li Gui's troops to rebel. Li Gui was desperate and was defeated and captured, and was beheaded by Li Yuan in Chang'an.

Although Xue Ju in Longxi was very powerful, he was cruel and forced to collect bribes. All the men in Hehuang drove them to join the army, and the public anger was extremely high in the Longxi area.

Although Xue Ju defeated the Tang army in the Battle of Sumiwara, he was killed by the assassin sent by Li Shimin. The Tang army then launched a large-scale counterattack. Xue Ju's army was defeated. His son Xue Rengao led the remnants to retreat to Xiping County. The subordinates all betrayed their relatives. Xue Rengao was killed by his general Zong Luohu and presented his head to Li Shimin.

Both Hehuang and Hexi were pacified, and the morale of the Tang army was greatly boosted. Li Shimin led an army of 80,000 to divide troops into three groups to fight against Liang Shidu. Duan Decao, the general of Li Shimin, defeated Liang Shidu, the cousin Liang Shidu, in Liangchuan County, Huining County, and killed 5,000 enemies. Another army was commanded by General Lin Xingcan of the Cavalry, and defeated the powerful general Xin Liaoer in Pingliang County. Xin Liaoer only led hundreds of cavalry to flee north.

The third route was led by Qu Tutong, the Minister of War, to fight against the 30,000 cavalry led by Liang Shidu in Honghua County. The two sides fought fiercely for three days and three nights. Li Shimin led reinforcements to the army, and Liang Shidu was defeated and returned to the north. On the one hand, he asked the Turks for emergency assistance, and on the other hand, he summoned the remaining troops to resist the guards of Lingwu County.

Li Shimin's 80,000 troops immediately came to Lingwu County. At this time, the Turkic Shibi Khan became sick due to his defeat in the internal throne of the Turkic Republic and died soon afterwards. His brother succeeded him to the throne and was called Chuluo Khan. The internal turmoil of the Turkic Republic was in chaos and had no time to look south.

However, Zhang Xuan had destroyed the Khitan and occupied Liaodong. The Khan of Chuluo did not want the Tang army to grow up in the west, so he sent his brother Mo Hedushi to lead an army of 30,000 to Lingwu County to assist Liang Shidu.

At the same time, a 800-li emergency report sent from Chang'an arrived in Lingwu County.

Li Shimin's army was stationed in Mingsha County, which is located at the southernmost point of Lingwu County, with few oasis and many Gobi Deserts. It was August, and the area around Lingwu County was dry and hot, and the earth was like a fire, sweeping thousands of miles in a radius. The Tang army was not accommodating, and there were many people with heatstroke, and their combat effectiveness dropped rapidly.

However, heat stroke was not just a difficulty encountered by the Tang army. The Liang Division took advantage of the cavalry and familiar terrain and sent more than a dozen small-scale cavalry teams to go south to harass the Tang army's food transportation. These cavalry teams were very familiar with the terrain and were elusive. They destroyed three Tang army food and grass transportation teams in a row, causing difficulties in the logistics supply of the Tang army.

In the big tent, Li Shimin walked back and forth with his hands worriedly. At this time, Qu Tutong, Duan Decao, Changsun Wuji and Zhang Gongjin quickly walked into the big tent. Li Shimin looked back at everyone and waved his hand and said, "Please sit down everyone!"

Seeing that Li Shimin had a worried look on his face, Changsun Wuji asked, "Is Your Highness worried about insufficient food?"

Li Shimin smiled bitterly, "There are too many troubles, not just one piece of food."

At this time, Qu Tutong slowly said: "When Zhang Xuan pacified the bandit Sun Xuanya in Langya County, he failed because of difficulties in food transportation. Later, they used the method of building military forts in the mountains to garrison grains, and advanced step by step to the south, and finally solved the food problem and defeated Sun Xuanya and Wang Bo in one go. Beizhi believed that this step-by-step method was worthy of our imitation. The biggest difficulty of Lingwu County was that it was hanging in the north, with a large Gobi desert and Longyou in the middle. If the problem of food transportation was not solved, we would not be able to take Lingwu County."

Li Shimin nodded. He admired Qu Tutong's practical attitude, not to reject Zhang Xuan because he was an enemy. Everyone can learn from each other's advantages. At this time, he saw Duan Decao want to speak but stopped, so he asked, "What do General Duan want to say?"

Duan Decao bowed and said, "Food transportation is indeed a big problem. Consider whether we can use the Yellow River transportation to solve this problem. I have observed that the section of the Yellow River from Jincheng County to Lingwu County is smooth and is very conducive to water transportation. The Liang Shidu and the Turkic army are both mainly cavalry, and water war is their weak link."

Before Duan Decao could finish his words, everyone praised it unanimously. This is a good idea. Why didn’t they think of it before?

At this time, Li Shimin waved his hand again and said to everyone: "My worries are not food issues, nor is the incompatibility of the soldiers, nor is it the Turkic cavalry coming to help. It is because I just received the emperor's will sent from Chang'an. My father urged me to withdraw my troops back to Chang'an immediately."

Everyone was stunned and asked in unison: "Why is this?"

Li Shimin took out the news that he had just received the 800-li urgent report and handed it to everyone: "The situation in the Central Plains suddenly changed. Zhang Xuan and Wang Shichong joined forces to hunt the Wagang army, which means dividing the Central Plains. The father did not want the Tang army to miss this division feast, so he asked me to return to Chang'an."

Everyone looked at each other. The enemy in the west had not completely calmed down, so why did they start to be moved by the Central Plains again?

Changsun Wuji said anxiously: "If we withdraw our troops just now, we may fail and the Liang army will recover. Although we are facing difficulties now, the Liang army is even more difficult. His army is less than 20,000. The Turkic army is far away in Hetao and hesitates and refuses to go south. As long as we wait until the autumn is cooler, we can defeat the Liang army in one battle, and your highness cannot withdraw its troops!"

Zhang Gongjin also advised: "Although grain transportation is difficult now, we can borrow large sheepskin rafts from the Hu people from Hexi to transport grain. It is like walking on flat ground in the Yellow River. There are still 100,000 stones of grain stored in Jincheng County to transport the grain. Our food problem will be solved immediately. As for the local environment and the local environment, as Changsun Changshi said, after the cold weather, the heat will fade away, and the combat power of soldiers will gradually recover. Now the withdrawal of troops will inevitably fail."

Qu Tutong also advised, "Since ancient times, there have been generals outside, and the king's orders have been unacceptable. Your Highness can only explain the specific situation to the Lord clearly and believe that the Lord can understand Your Highness."

Everyone persuaded him, but Li Shimin just smiled bitterly. Changsun Wuji reacted first and asked in a low voice: "Your Highness, does the emperor have to withdraw his troops? There is no room for harmony?"

There was silence in the tent, and everyone looked at Li Shimin. Li Shimin sighed and said to everyone: "Actually, I understand my father very much. It has been less than a year since the emperor ascended the throne. The majesty of the monarch is the most important thing. It must be said one thing, and even if you know it is a mistake, it must be implemented without fail.

But now even my son is a general outside, and the king is not willing to accept his orders. How would his father feel? He may not blame me, but he will definitely take his anger on you. This is not the result I want to see, this is one of them.

The second is the change in the Central Plains. Everyone knows that the father’s desire for eastward advancement. Even when Zhang Xuan was expeditioning to Goguryeo, his father couldn’t help but attack Huguan. What’s more, now it’s time to divide the Central Plains, how could he stay out of the matter?”

"But Luoyang is east of us. How can we participate in the division of the Central Plains?" Duan Decao asked in confusion.

Qu Tutong next to him knew the situation in the Central Plains very well and said in a deep voice: "The emperor's idea should go to Wuguan to Nanyang, seize a piece of the southwestern part of the Central Plains, and then use this as the foundation to march into Jingxiang. Another possible reason is to take advantage of Wang Shichong's troops to the Central Plains and Luoyang was empty."

Li Shimin nodded, "It should be that there are two possibilities, so my father asked me to return to the army immediately. Otherwise, it would be enough to capture the Nanyang counties with the existing army in Chang'an."

"Have your highness decided to return to Chang'an?" Changsun Wuji knew Li Shimin, and he knew that Li Shimin must have made a decision.

Li Shimin sighed, "I decided to withdraw my troops and return to the south and attack Liang Shidu in the future."

He then said to Duan Decao: "I will ask my father to appoint General Duan as the governor of Pingliang. General Duan can lead an army of 20,000 to guard the two counties of Pingliang and Honghua, and will not give Liang Shidu a chance to go south."

Duan Decao stood up and saluted, "Your Highness will never be disappointed!"
Chapter completed!