Once Vietnam did succumb to foreign rule, however, it proved unable to escape from it, and for 1,100 years, Vietnam had been successively governed by a series of foreign powers: the Hans, Eastern Hans, Eastern Wus, Cao Wei, Jins, Liu Songs, Southern Qis, Liangs, Suis, Tangs, and Southern Hans; leading to the losses of its writing system, language, and national identity. At certain periods during these 1,100 years, Vietnam was independently governed under the Triệus, Trưng Sisters, Anterior Lýs, Khúcs and Dương Đình Nghệ - although their triumphs and reigns were brief.