In the Western Regions, the most important in addition to the Seven Guards of Kansai was the Eastern Chagatai Khanate, followed by the smaller states of Liucheng, Huozhou, and Turpan.

Liucheng: During the Yuan Dynasty, it was Liucheng Wanhu Mansion, and Yongle began to pay tribute in the fifth year.

Huozhou: During the Yuan Dynasty, it was the governor's office of Hara Huozhou, and Yongle began to pay tribute in the fifth year.

Tulupan: During the Yuan Dynasty, it was Tulupan Wanhu Mansion, and Yongle began to pay tribute in the fourth year.

Even the Eastern Chagatai Khanate was divided into three parts in terms of territory and power:

The first is the headquarters of Yili Jiangli, which starts from Beita Mountain in the east, reaches Tashkent in the west, borders the Emin River in the north to the line of Balkhash Lake, and covers the Tianshan Mountains in the south;

the second is the territory of the Dugrat Division, including the area around the Tarim Basin, the Pamir Plateau and the Fergan region west of it;

The third is the Uighur tribe, that is, the Turpan Basin, which is worth mentioning that the Uighurs were called during the Tang Dynasty.

Like those that were interspersed between the Ming and Eastern Chagatai Khanates, Turpan, Huozhou, and Liucheng were both vassal to the Eastern Chagatai Khanate and tribute to the Ming Dynasty.

Therefore, the Seven Guards of Kansai was an indispensable barrier for the Ming Dynasty, which could effectively prevent the various forces in the Western Regions from infiltrating eastward, and its role was crucial.

In fact, the Ming Dynasty had the opportunity to establish a stable local government in the Western Regions during the Hongwu period, and when it comes to this, we have to mention the Lingbei Battle launched by Ming Taizu against the Northern Yuan.

In the fifth year of Hongwu, the Ming army again made a northern expedition to the Northern Yuan, aiming to complete the unfinished historical achievements of the Han and Tang dynasties, the Mongolian desert of Yongqing, because the main battlefield of the Northern Expedition took place in Lingbei and Lin, so it was called "the battle of Lingbei" in history.

The Ming army's northern conquest was divided into three routes, and Ming Taizu ordered Xu Da, the Duke of Weiguo, to be the general of the conquest and go out of the middle road; Cao Guogong Li Wenzhong was the left deputy general and went out of the east road; Feng Sheng, the Duke of Song, was the general of the expedition to the west and went out on the west road.

According to the plan, Xu Da led the main force of the Ming army to lure the main force of the Northern Yuan Dynasty to fight near the border, Li Wenzhong, the deputy general of the left, led the Eastern Route Army to attack the Northern Yuan court, and Feng Sheng, the general of the expedition to the west, led the Western Route Army to confuse and contain the kings of the Northwest Mongolia, and cooperated with the Middle Route Army to fight.

In the three-way army, Xu Da's middle route army is the main force, Li Wenzhong's army on the east road is a surprise soldier, and Feng Shengjun on the west road is responsible for the containment task.

The Central Route Army was faced with an encounter battle, and the strategic purpose of annihilating the main force of the Mongolian army was the key and key to determining whether this campaign could succeed.

The Eastern Route Army, unlike the Middle Route Army, did not aim at military operations, but aimed at eliminating the Northern Yuan Khanate under the cover of the Middle Route Army.

The Western Route Army was the lightest of the three armies, and it was only a flank force that served to contain Zuò, and it undertook these two major tasks, one was to occupy Gansu, and the other was to contain the Mongol forces in Gansu to prevent it from expanding the Timurid army in the east.

In order to facilitate the Western Route Army to better carry out the cover task, Feng Sheng's general name is different from before.

Xu Dapei "conquered the general seal" and Li Wenzhong wore the "left deputy general seal", but Feng Sheng did not wear the "right deputy general seal" during Hongwu's three-year Northern Expedition, but instead admired the "general seal of the expedition to the west", deliberately distinguishing it from the other two Ming armies.

After entering the Mongolian desert, Xu Da's Middle Route Army suffered a heavy defeat in Lingbei and Lin, and Li Wenzhong's army had to fall into the dilemma of fighting alone because of the lack of cover of the Middle Route Army, and suffered heavy casualties.

Since the Western Route Army did not enter the desert but carried out its mission in Gansu, it was not affected by the battles between the middle and eastern routes, but won a heavy victory, occupying almost the entire territory of Gansu Province.

The Battle of Lingbei was the biggest defeat in the history of the Ming army, with many high-ranking generals killed in battle, and tens of thousands of soldiers died.

These soldiers who died in battle were the elite soldiers who followed Emperor Hongwu in the early Ming Dynasty and were able to confront the Mongol army on the battlefield, which in turn prompted the Ming Dynasty's northwest strategy policy to change from the offensive strategy of purging Mongolia and occupying Inner Asia advocated by Wuchen to the strategy of relying on the Great Wall to implement near-border defense advocated by Wenchen, which laid the pattern of long-term confrontation between Ming and Mongolia for more than 200 years in one fell swoop, and had an important impact on the trend of history.

For Feng Sheng, what he feared most in Gansu was the Eastern Chagatai Khanate to the west.

However, when Ming Taizu launched the Battle of Lingbei, the Great Khan of the Eastern Chagatai Khanate, Hammaruddin, launched a fierce attack on the Timurid Empire in the west and occupied a large territory of the Timurid Empire, which was very vigorous.

Feng Sheng was shocked when he heard the news of the disastrous defeat in the Battle of Lingbei, and because he was afraid of the Eastern Chagatai Khanate's eastward advance into Gansu, he chose the policy of abandoning the city to avoid losing grain to the ground.

Fu Youde, the Marquis of Yingchuan, who had won seven battles and seven victories in Gansu, did not advance westward after occupying Gua and Shazhou, also to avoid war with the Eastern Chagatai Khanate

After Feng Sheng withdrew his troops, the Eastern Chagatai Khanate did not advance eastward, but broke out a war with the Timurid Empire in full swing, and there was no time to take care of the affairs of the Western Regions.

For the Eastern Chagatai Khanate, its primary strategic goal was to capture the Timurid Empire.

The Eastern Chagatai Khanate and the Timurid Empire in the west originally belonged to the Chagatai Khanate, one of the four khanates of the Mongol Empire, and Hammaruddin usurped the throne as a non-golden family, which was not only opposed by many nobles within the Eastern Chagatai Khanate, but also posed a threat to Hammarudin by the Timurid Empire's self-proclaimed status as a golden family.

Therefore, whether from the perspective of unifying the Chagatai Khanate or from the perspective of maintaining the legitimacy of the Khanate, Hammaruddin regarded the westward march into the river and the unification of the Chagatai Khanate as the primary strategic goal of the Eastern Chagatai Khanate.

In addition, the Eastern Chagatai Khanate was based on pastoral status, but the geographical conditions were poor, while the agricultural conditions in the Transoxiana region were very superior, and there were rich resources that the Eastern Chagatai Khanate did not have, so the occupation of the Transoxiana region was also very helpful for the Eastern Chagatai Khanate to strengthen its economic strength.

Both politically and economically, the primary strategic goal of the Eastern Chagatai Khanate was the Hezhong region, and Gansu was only a marginal area, and the influence of the Eastern Chagatai Khanate was extended to the Shazhou and Hami regions west of Jiayuguan during the reign of Timur Khan.

Even so, the power of the Eastern Chagatai Khanate only penetrated in, and it was still the nobles of the Chagatai Queen's group who dominated the region, and Gansu had never had anything to do with the Chagatai Khanate.

It is clear that Hammaruddin could only consider moving east into Gansu after unifying the Eastern Chagatai Khanate and the Timurid Empire, and Feng Sheng apparently did not see this.

History proves that Feng Sheng made a wrong decision, in the late Hongwu period, as Timur defeated Hammaruddin, the young son of Timur the Bald Black inherited the throne of the Eastern Chagatai Khanate, and adopted the method of marriage with Timur, and only after eliminating the threat from the west did he begin to pass through the eastern region, detain the Ming envoy Fu An, occupy the territory of Lupan, and attack Hami.

The strategic choice adopted by the Timurid Empire was also to first appease the Eastern Chagatai Khanate, then advance westward to eliminate the Ilkhanate, inflict heavy losses on the Kipchak Khanate, and unify Central and West Asia before advancing eastward.

It is worth mentioning that in the third year of Yongle, Timur, the great khan of the Timurid Empire, led more than 200,000 soldiers to launch an eastern crusade against the Ming Dynasty, wanting to conquer the Ming Dynasty, but unfortunately died of illness in the army the following year, thereby eliminating a war between the Timurid Empire and the Ming Dynasty.

Therefore, although only Feng Sheng's Western Route Army won the victory in Hongwu's five-year northern expedition, Feng Sheng's return to Beijing was not rewarded like the defeated generals Xu Da and Li Wenzhong.

According to the record of "Ming Taizu Record", "Ren Shen ordered to reward 1,435 soldiers of Gansu Jingwei and 44,000 taels of platinum. When the princes, governors, commanders, and thousands of households were not rewarded for their horses, mules, cattle and sheep. The reason for the oracle said: 'For the general, he does not selfish himself, but what about things?' In the past, the sacrifice was obeyed as a general, and the country was worried; Cao Bin Ping Nan Tang, contained only books. If you can do the ancients, you will make the name endless. If you don't appreciate it now, you should bow down and make up for it with thought. All the generals bowed their heads and apologized and withdrew. ”

This historical material shows that the greedy horses and other things were collectively committed by the generals of the Western Route Army, not Feng Sheng alone, but a discerning person can see at a glance that the responsibility of the generals of the Western Route Army for not being rewarded is entirely because of Feng Sheng.

However, "the general of the time is not good for the army, and the left deputy general Wen Zhong has lost a lot, and he is the only one who wins by the news, and it is said that he will not be rewarded for hiding his private captives and horses." "Feng Sheng's lack of reward for corruption is a common record in the historical books of the Ming Dynasty.

Or, because Ming Taizu's favorite Xu Da and Li Wenzhong were defeated, they deliberately suppressed Feng Sheng and Fu Youde, after all, Ming Taizu's way of dominating was to play perfectly.

If Feng Sheng made any serious mistakes in Gansu, it was that he did not manage the local area when he retreated from Gansu, which made the territory that the Ming army had managed to fight down with great difficulty be handed over, and also made the Ming Dynasty's northern expedition return in vain, which led to the anger of Ming Taizu, and then severely punished him.

The terrain and methods of Feng Sheng's Western Route Army were significantly different from Xu Da's Middle Route Army and Li Wenzhong's Eastern Route Army, both of which fought deep into the Mongolian desert and did not set up garrisons on the way to the army, but aimed at annihilating the Mongol army and attacking the Northern Yuan Khanate.

After the defeat and retreat of the Middle Route Army and the Western Route Army, the Ming army could not stay in the Mongolian desert, and the Mongolian army took the opportunity to move south to the Great Wall.

However, the Western Route Army's area of operation has always been in Gansu, the terrain of Gansu is different from the rolling grasslands of Mongolia, and the narrow Hexi Corridor is very suitable for farming, which is also the fundamental reason why the Han and Tang dynasties were able to occupy Gansu for a long time and use it as a barrier to cut off the northern and western nomadic forces.

The developed agriculture and habitable towns provided the conditions for the Ming army to be stationed for a long time, and the Ming army implemented the Ming Taizu's military system, and Feng Sheng should operate in the captured areas, and adopt the method of expanding the territory and defending anywhere.

After the Battle of Lingbei, although the Mongolian army went south to the Great Wall, the threat to the Ming Dynasty was mainly in Datong and Xuanfu east of Gansu, so the Western Route Army in Gansu was not threatened by the Mongolian army, so when the Western Route Army retreated, it could leave enough troops to defend Gansu, and should not completely give up and withdraw in a hurry.

In Li Yuntian's view, the current strategic focus of the Ming Dynasty is the Tatars and Warats in the north, and they have not yet had the energy to deal with the threat from the Western Regions, so the role of the Seven Guards of the West is particularly important.