The Yongle Emperor's Northern Inspection and Border Defense

Timeline

1. 1412Beijing (Shuntian Prefecture) · BeijingIn the third month of the tenth year of Yongle, the Chengzu emperor raised Shuntian Prefecture from the fourth to the third rank, equal to Yingtian Prefecture, and launched a new round of large-scale construction of Beijing city. This elevated the political status of Beijing as the 'temporary capital,' providing a capital foundation for the eventual relocation and the strategy of the Son of Heaven defending the frontier, and also relied on the previous year's dredging of the Huitong River to secure grain transport of construction materials.
2. 1412Great Wall line of the Ji and Xuan garrisons · HebeiAfter relocating the capital to Beijing, the Yongle reign continuously repaired the Great Wall defense system; commanders of the Ji and Xuan garrisons inspected their defense zones, raising castles and deepening moats. Previously, Mutianyu Pass, Zhuangdaokou, and Huanghua Town fortress had been newly built, and Gubeikou narrowed. This year, under a strategy of 'offense as defense,' the court maintained deterrence against the Tatars and Oirats along the frontier and settled submitting Mongol groups at border guards and battalions.
3. 1412Between the southern steppe and the capital · Inner MongoliaIn the eighth year of Yongle, the Chengzu emperor personally campaigned against the Tatars, crushing Bunyashi at the Onon River, but after returning, the Oirats took the opportunity to grow stronger. By the tenth year of Yongle, the court hastened to assemble troops and gather grain and funds, relying on Huitong River grain transport to secure northern military supplies, making full military preparations for a second personal campaign against the Oirats in the second month of the twelfth year of Yongle, reflecting the court's continued northern strategy amid the capital relocation.