The civil war amongst the Lê-Trịnh and Mạc dynasties resulted in 1592, when the army of Trịnh Tùng conquered Hanoi and executed king Mạc Mậu Hợp. Survivors on the Mạc royal loved ones fled into the northern mountains inside the province of Cao Bằng and continued to rule there till https://vitnam09753.liberty-blog.com/31137634/about-6623