Tĩnh Hải quân
Tĩnh Hải quân or Jinghai Prefecture was an administrative division of the Tang dynasty of China administered by Chinese governors, which then later became a quasi-independent regime ruled by successive local Vietnamese warlords and monarchs. It was centered around what is now northern Vietnam from 866 to 967 during the late Tang period and lasted until the late Five Dynasties and Ten Kingdoms period when Đinh Bộ Lĩnh established the Đinh dynasty.