Previously a captain of the imperial guard (Praetorian Prefect equivalent) of one of the Lê dynasty emperors, he gradually rose to a position of great power.

[2][3] He was born Mạc Đăng Dung (莫登庸) on 23 November 1483 (Quý Mão in the sexagenary cycle) at the village of Cổ Trai, Nghi Dương district (modern Kiến Thụy, part of Haiphong city) as a fisherman's son.

With the enthronement of the young emperor Lê Chiêu Tông in 1516, a power struggle in the court, along with Trần Cao rebellion lead the country to the level of a civil war.

Lê Chiêu Tông fled the court with the support of the warlord Trịnh Tuy to Thanh Hóa where he fought against Mạc Đăng Dung until being captured in 1526.

Some government officials committed suicide rather than acknowledge Mạc Đăng Dung as emperor, others fled south and joined the resistance.

However Mạc Đăng Dung, using submissive behavior and bribery, managed to obtain a temporary recognition of his rule from the Ming dynasty in 1528.

Adding to the problems of military defeats, an official Chinese delegation determined that Mạc Đăng Dung's usurpation was not justified and so, in 1537 a very large army was dispatched to Vietnam under the pretense of restoring the Lê family to power.