Rise of Oirat Mongol Power (1390s)

Timeline

1. 1391–1393Northern steppe · Mongolian PlateauAfter the Battle of Buir Nor in 1388, Northern Yuan khagan authority existed in name only; eastern Tartars and western Oirat each enthroned puppet khans. The steppe entered an era of tribal rivalry, giving the Oirat political room to expand.
2. 1393–1397Khovd River basin · Mongolian PlateauThe four Oirat tribes (Dzungars, Dörbet, Torghuts, and Khoshuts) formed an alliance on the western steppe, electing a strong leader to direct military and political affairs. The alliance controlled vast pastures from the Altai to Khovd, rapidly concentrating population and herding resources.
3. 1397–1400Southern steppe and northern edge of the Hexi Corridor · Inner MongoliaOirat eastward expansion clashed with the Tartars while also skirmishing with Ming frontier garrisons. The Ming court pursued a divide-and-co-opt strategy, exploiting steppe divisions to secure the northern frontier, while the Oirat used Ming pressure to check the Tartars and expand their own influence.