Judy, the emperor of the Ming Dynasty, held the throne, but his relationship with the gentry in the south of the Yangtze River was not good. In addition, their influences are intertwined, and many of them sympathize with Wen Jian Emperor Zhu Yunwen. In a word, Judy is a cat on hot bricks here.
And Beijing is his own lair. Judy is the first generation prince of Daming, and Beijing is the administrative and military center of Yan Di. Having lived in Beijing for more than 20 years, he is not only familiar with it, but also confident that the prince has control over the local military and political affairs and has a mass base. As the saying goes, a golden nest is not as good as your own kennel. No matter how beautiful the scenery in the south of the Yangtze River is and how windy and dusty it is in Beijing, you should be comfortable when you go back. Don't look at the gentry's face any more. When you come to Beijing, it is Judy's home. If the gentry want to be an official in Beijing, they must be careful and obedient.
2. Military reasons In the early years of Yongle, the Northern Yuan was still very powerful and often invaded the mainland. When Judy was a prince, she often fought with them, and her resume was rewarded, which indirectly exercised Judy and his army. After Judy proclaimed herself emperor in Nanjing, she never forgot the war in the north, and her military action against Yuan in the north never stopped.
However, Nanjing is too far away from the northern battlefield. Ancient communication technology was backward. It took more than a month before the court issued an order to go back and forth. As a king who likes to take the lead, he often takes the lead and takes the lead. This situation is intolerable to Judy.
As the military center of the Ming Dynasty, Beijing itself is very suitable as the central city of military command in the north, and it can quickly contact the battlefield. When Cheng Zu first arrived in Beijing, he actually planned to live here temporarily, but he didn't formally build Beijing. However, war is changing rapidly. In order to cope with the huge logistics and government affairs, many institutional personnel, including the prince, came to Beijing to support Ming Chengzu, who had made great achievements ahead, and never returned. After a long time, it became the official capital of Daming.
3. Economic reasons You said in your question that Beijing is blank, which should be inaccurate. Before Beijing became the capital of Daming, it went through the stages of Liaoning, Nanjing, Jinzhongdu, Yuandadu and Taizidu. Although there are many wars in the middle, it can't be compared with the southern cities, but the construction of several towns in the north is still good. Judy has been a prince here for more than 20 years, laying a very good foundation, and it is not blank.
The northern part of Beijing is the Yanshan Mountains, and the southern part is close to the hinterland of the densely populated and economically developed North China Plain, and there is canal communication nearby. As the capital, material transportation is usually not necessarily the best, but on the whole it is quite suitable.