Quy Hóa

Quy Hóa encompassed the upper Red River country of northwestern Đại Việt, including Trấn Yên and the mountain districts farther upstream. The river provided a route between the delta and Yunnan, winding between forested ridges and settlements along its banks. In 1426 the Lam Sơn commanders advanced into Quy Hóa and neighbouring districts to block Ming reinforcements approaching from the northwest during the struggle for independence.