莫登庸
In the early 16th century, the Later Lê dynasty started weakening. The degenerated Lê dynasty, which endured under six rulers between 1497 and 1527, in the end was no longer able to maintain control over the northern part of the country, much less the new territories to the south. The weakening of the monarchy created a vacuum that the various noble families of the aristocracy were eager to fill. Soon after Lê Chiêu Tông fled south with the Trịnh and the Nguyễn in 1522, Mạc Đăng Dung proclaimed the Emperor's younger brother, Le Xuan, as the new Emperor under the name Lê Cung Hoàng. In reality, the new Emperor had no power. Three years after Mạc's forces killed his older brother, Lê Chiêu Tông, Mạc Đăng Dung ended the fiction that Lê Cung Hoàng actually ruled by killing him in 1527. Mạc Đăng Dung, being a scholar-official who had effectively controlled the Le for a decade, then proclaimed himself the new Emperor of Vietnam in 1527, and established the Mac Dynasty.