The Mongolia entered the southern aera alongside the Yellow River between Ningxia and Middle Hebei had gotten direction with
the
Ming Dynasty northern border defense situation.Zhuyuanzhang establish the north defense line hour to river set the problem is thoughtful of not enough, the Zhudi ascend the throne the empress big rather and all Daning Militiary Establishment is with the Dongsheng , Xinghe withdraw face hinterland, and make the Ming Dynasty defense Mongolia of the north the defense line appear two greatest indentations, and cause the virtuous year of Xuande to open the even Weiping to withdraw face hinterland, flashing it after becoming the north hazardous to the utmost lose, river set the problem to highlight out. Concerning the time of Mongolia tribe entering the Hetao, relative historical records carry rather many differently. In fact, Mongolia entered the Hetao as early as Xuande years. From the early years of Zhengtong Mongolia began to intrude and plunder the frontier. In the days of Jingtai and Tiansun, several more famous mongol tribe frequently worked in the area.After Chengsun,Hetao become Mongolia base of permanence. Mongolia after enter the river set, to the clear of the north the region result ined tremendous of pressure, formation the Ming Dynasty middle period continue 100 remaining years of life it long northern part border defense crisis.