1620s Oirat Four-Part Structure and Prelude to Dzungar Rise

Timeline

1. 1621–1624Western Mongolian Plateau · MongoliaIn the early 1620s, the four Oirat tribes maintained separate nomadic alliances around the Irtysh River and Altai Mountains; after the Northern Yuan's collapse, each established contacts with Khalkha Mongols, Tibet, and Central Asian khanates, and the 1620s marked the transition of the four from a loose alliance to independent powers.
2. 1624–1627Khoshut pastures (Qinghai–northern Xinjiang) · KhoshutIn the mid-1620s, the Khoshut under leaders such as Baibagas consolidated control over northern Xinjiang pastures, while the Torghut began expanding toward Siberia; in the late 1620s some Torghut began planning a westward migration to the Volga basin (formally departing in the 1630s), reflecting intensifying resource competition among the four tribes.
3. 1628–1630Dzungarian Basin · DzungariaBy the late 1620s, the Dzungar under Khara Khula had significantly strengthened, competing with the Khoshut and Derbet for pastures and trade routes; by decade's end the Dzungar possessed the potential to later unite the Oirat, foreshadowing Galdan's establishment of the Dzungar Khanate in the 1670s.