Both the Trịnh and the Nguyễn families were descended from close friends and aides to the hero-Emperor Lê Lợi who freed Vietnam from Chinese rule and started the Lê Dynasty in 1428. By 1520 a succession of weak kings had brought the country into a state of civil war (see Lê Dynasty's civil war). For the next 20 years the Trịnh and Nguyễn families fought as allies against the usurper Mạc Đăng Dung. In theory, they both were fighting on behalf of the Lê Emperor (Lê Trang Tông) but in reality, the Emperor was a figurehead with little or no power. [citation needed]