 He put his capital at Cổ Loa, the old capital of Âu Lạc in the 3rd century BC and set up a centralized government.After Ngô Quyền's death, Vietnam became embroiled in the Anarchy of the 12 Warlords.In 968, Đinh Bộ Lĩnh unified the country and declared himself as Emperor of Đại Cồ Việt.