Yongle Emperor
Wars against the Mongols

Mongol invaders were still causing many problems for the Ming Empire. The Yongle Emperor prepared to eliminate this threat. He mounted five military expeditions into the Mongol steppes and crushed the remnants of the Yuan dynasty that had fled north after being defeated by the Hongwu Emperor. He repaired the northern defences and forged buffer alliances to keep the Mongols at bay in order to build an army. His strategy was to force the Mongols into economic dependence on the Chinese and to launch periodic initiatives into Mongolia to cripple their offensive power. He attempted to compel Mongolia to become a Chinese tributary, with all the tribes submitting and proclaiming themselves vassals of the Ming Empire, and wanted to contain and isolate the Mongols. Through fighting, the Yongle Emperor learned to appreciate the importance of cavalry in battle and eventually began spending much of his resources to keep horses in good supply. The emperor spent his entire life fighting the Mongols. Failures and successes came and went, but after the emperor's second personal campaign against the Mongols, the Ming Empire was at peace for over seven years.
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