Dayan Khan
Under Dayan Khan, the Khalkha were organized as one of three tümen of the Left Wing. Dayan Khan installed the fifth son Alchu Bolad and the eleventh son Geresenje on the Khalkha. The former became the founder of the Five Halh of Southern Mongolia and the latter became the founder of the Seven Halh of the Northern Mongolia. They were called Inner Khalkha and Outer Khalkha respectively, by the Manchus.