勤王運動
In mid-1911, Sanh formed a secret society on the unverified pretense that he was a descendant of Hàm Nghi, the boy emperor of the 1880s. Led by Tôn Thất Thuyết and Phan Đình Phùng—two high-ranking mandarins—Hàm Nghi's Cần Vương movement battled against French colonisation in the decade leading up to 1895. Their objective was to expel the French authorities and establish Ham Nghi as the emperor of an independent Vietnam. This failed, and the French exiled the boy emperor to Algeria, replacing him with his brother Đồng Khánh. From then on, the French retained the monarchy of the Nguyễn Dynasty, exiling any emperors who rose against colonial rule and replacing them with more cooperative relatives. Sanh also claimed descent from the Lê Dynasty, which ruled Vietnam in the 15th and 16th centuries. He was a strong warrior, further presenting himself as the founder of China's Ming Dynasty.