The civil war amongst the Lê-Trịnh and Mạc dynasties led to 1592, when the military of Trịnh Tùng conquered Hanoi and executed king Mạc Mậu Hợp. Survivors with the Mạc royal relatives fled into the northern mountains during the province of Cao Bằng and continued to rule there till 1677 https://vi-t-nam98753.aioblogs.com/84499155/how-much-you-need-to-expect-you-ll-pay-for-a-good-việt-nam