1449 AD, that is, the protagonist of our story, Ming Yingzong, was in the fourteenth year of orthodoxy. After fleeing to the north, Mongolia was divided into Tatar and Wala. In view of the fact that the leaders of the Mongolian Wala first joined forces with the Mongolian ministries and attacked the northern part of the Ming Dynasty in four ways, many towns on the border were suddenly looted by Mongolian soldiers, which posed a great threat to the security of the Ming Dynasty.

At the instigation of eunuch Wang Zhen and others, Ming Yingzong hastily decided to lead a 500,000-strong army to personally expedition Wala without fully understanding the enemy's situation and making early preparations. Emperor Yingzong's personal expedition failed unexpectedly but reasonably. Sixty-six ministers of the Ming army, including the ministers of the Ministry of War and the Ministry of Housing, died in battle. The most incredible thing is that the Emperor Yingzong of the Civil Fort outside Juyongguan was also captured by Wala and became a prisoner, which is called "the change of the Civil Fort" in history.

Second, Mongolian Tatar and Wala

After the Mongolian aristocrats fled to the north, Mongolia was divided into two parts due to the struggle for power and profit, in which the Tatar (the direct descendant of Kublai Khan) in the east and the Wala (the descendant of Kublai Khan's throne contender Alibaba Buge) in the west fought against each other. Among them, Wala chose to submit to Daming for the Tatar struggle, and Ming Chengzu named Mahamu, the leader of Wala, as King Shunning.

In A.D. 14 18, Mahamu's son took over the title of King Shunning. A few years later, with the support of the Ming Dynasty, he successfully defeated the Tatars, annexed the Tatars and became a powerful faction in the upper and northern Mongolian grasslands. In AD 1439, after the death of Tuohuan, his son also succeeded to the throne, continued to carry out the war of conquest and annexation, and successfully conquered various Mongolian tribes in Monan, eventually becoming the actual ruler on the grassland. At this time, the Tatar Department had been annexed by Wala. To be precise, the Tatar Department was subordinate to Wala Department. Of course, since then, the Wala Department has declined, and the Tatar Department has re-emerged and separated from the Wala Department.

3. What were the Tatars doing during the change of the Civil Fort? The author infers that it should be arranged to fight elsewhere first.

Ming Yingzong's personal expedition route passes through Juyongguan, Huailai, Xuanfu, Tianzhen, Yanghe and Datong in turn; The turn-back route is Datong, Xuanfu and Civil Fort, which is just in the key offensive war zone that attacked the Ming Dynasty first, and it is bound to put the most elite and reliable soldiers here to fight the Ming army first. In view of the long-term struggle and opposition between the Wala Department and the Tatar Department and the final merger of Wala to the Tatar Department, the hatred between the Tatar Department and Wala Department is even deeper.

Then what is the Tatar Department doing at this time? Looking through historical materials and recent research materials, this problem has not been involved. Considering the purpose of fighting first and the prevention of the Tatar Department, the author infers that the Tatar Department should be arranged to attack the eastern Liaoning area of the Ming Dynasty first.

The reasons are as follows: First, the commander-in-chief of the East Route Army, Tuotuo Buhua (who has been promoted to the Mongolian Khan position at this time), is a direct descendant of Kublai Khan and the supreme ruler of the Tatar Department, and can command the Tatar soldiers; Second, the supervision of the Ministry of Wuliangha can ensure that the orders can be effectively executed first and prevent the Tatar Ministry from taking the opportunity to rebel; Third, fighting in Liaodong nearby, the Tatar department is familiar with the environment, and it is easy to achieve results in the battle, so it can well cooperate with the Central Route Army.