The son of Emperor Khai Dinh, a vassal of the French colonial regime, and a concubine of peasant ancestry, Nguyen Vinh Thuy was educated in France and spent little of his youth in his homeland. He succeeded to the throne in 1926 and assumed the title Bao Dai (“Keeper of Greatness”). He initially sought to reform and modernize Vietnam but was unable to win French cooperation.

During World War II the French colonial regime exercised a firm control over Bao Dai until the Japanese coup de force of March 1945, which swept away French administration in Indochina. The Japanese considered bringing back the aging Prince Cuong De from Japan to head a new quasi-independent Vietnamese state, but they finally allowed Bao Dai to remain as an essentially powerless ruler. When the Viet Minh seized power in their revolution of August 1945, Ho Chi Minh and his colleagues judged that there was symbolic value to be gained by having Bao Dai linked to them. The Viet Minh asked Bao Dai to resign and offered him an advisory role as “Citizen Prince Nguyen Vinh Thuy.” Finding that the Viet Minh accorded him no role, and distrustful of the French, Bao Dai fled to Hong Kong in 1946. There he led a largely frivolous life, making appeals against French rule.

In 1949 the French accepted the principle of an independent Vietnam but retained control of its defense and finance. Bao Dai agreed to return to Vietnam in these circumstances in May 1949, and in July he became temporary premier of a tenuously unified and nominally independent Vietnam. Reinstalled as sovereign, Bao Dai continued his pleasure-seeking ways and became generally known as the “Playboy Emperor.” He left the affairs of state to his various pro-French Vietnamese appointees, until October 1955 when a national referendum called for the country to become a republic. Bao Dai retired and returned to France to live.