Treaty of Huế (1884) in the context of "French Union"

The Nguyễn dynasty (Vietnamese: Nhà Nguyễn or Triều Nguyễn, chữ Nôm: 茹阮, chữ Hán: 朝阮) was the last Vietnamese dynasty, preceded by the Nguyễn lords and ruling unified Vietnam independently from 1802 until the start of the French protectorate in 1883. Its emperors were members of the House of Nguyễn Phúc. During its existence, the Nguyễn empire expanded into modern-day Southern Vietnam, Cambodia, and Laos through a continuation of the centuries-long Nam tiến and Siamese–Vietnamese wars. With the French conquest of Vietnam, the Nguyễn dynasty was forced to give up sovereignty over parts of Southern Vietnam to France in 1862 and 1874, and after 1883 the Nguyễn dynasty only nominally ruled the French protectorates of Annam (Central Vietnam) as well as Tonkin (Northern Vietnam). Backed by Imperial Japan, in 1945 the last Nguyễn emperor Bảo Đại abolished the protectorate treaty with France and proclaimed the Empire of Vietnam for a short time until 25 August 1945.

The House of Nguyễn Phúc established control over large amounts of territory in Southern Vietnam as the Nguyễn lords (1558–1777, 1780–1802) by the 16th century before defeating the Tây Sơn dynasty and establishing their own imperial rule in the 19th century. The dynastic rule began with Gia Long ascending the throne in 1802, after ending the previous Tây Sơn dynasty. The Nguyễn dynasty was gradually absorbed by France over the course of several decades in the latter half of the 19th century, beginning with the Cochinchina Campaign in 1858 which led to the occupation of the southern area of Vietnam. A series of unequal treaties followed; the occupied territory became the French colony of Cochinchina in the 1862 Treaty of Saigon, and the 1863 Treaty of Huế gave France access to Vietnamese ports and increased control of its foreign affairs. Finally, the 1883 and 1884 Treaties of Huế divided the remaining Vietnamese territory into the protectorates of Annam and Tonkin under nominal Nguyễn Phúc rule. In 1887, Cochinchina, Annam, Tonkin, and the French Protectorate of Cambodia were grouped together to form French Indochina.

Tonkin (chữ Hán: 東京), or Bắc Kỳ (北圻), was a French protectorate encompassing modern Northern Vietnam from 1883 to 1949. Like the French protectorate of Annam, Tonkin was still nominally ruled by the Vietnamese Nguyễn dynasty. In 1886, the French separated Tonkin from the Nguyễn imperial court in Huế by establishing the office of "Viceroy" (經略衙, Kinh lược nha). However, on 26 July 1897, the position of Viceroy was abolished, officially making the French resident-superior of Tonkin both the representative of the French colonial administration and the Nguyễn dynasty court in Huế, giving him the power to appoint local mandarins. In 1887, Tonkin became a part of the Union of Indochina.

In March 1945, the emperor Bảo Đại rescinded the Patenôtre Treaty, ending the French protectorates over Annam and Tonkin, establishing the Empire of Vietnam, a Japanese-backed state. Following the surrender of Japan, ending World War II, the Việt Minh launched the August Revolution which led to the abdication of Bảo Đại and the declaration of independence of the Democratic Republic of Vietnam.

The Treaty of Huế, (Vietnamese: Hòa ước Harmand, Hòa ước Quý Mùi) concluded on 25 August 1883 between Vietnam (Nguyễn dynasty) and France, recognising a French protectorate over Vietnam being divided into Annam and Tonkin. Dictated to the Vietnamese by the French administrator François-Jules Harmand in the wake of the French military seizure of the Thuận An forts, the treaty is often known as the 'Harmand Treaty'. Considered overly harsh in French diplomatic circles, the treaty was never ratified in France, and was replaced on 6 June 1884 with the slightly milder 'Patenôtre Accords' or 'Treaty of Protectorate', which formed the basis for French rule in Vietnam until the 1949 Élysée Accords signed between France and emperor Bảo Đại.