The Nguyễn dynasty was the last Vietnamese dynasty, which was preceded by the Nguyễn lords and ruled the unified Vietnamese state independently from 1802 to 1883 before being under French protectorate. During its existence, the 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, Nguyễn dynasty was forced to give up the sovereignty over parts of Southern Vietnam by France in 1862 and 1874, and after 1883 the Nguyễn dynasty only nominally ruled the French protectorates of Annam (in Central Vietnam) as well as Tonkin (in Northern Vietnam). They later canceled treaties with France and were the Empire of Vietnam for a short time until 25 August 1945.

The Nguyễn Phúc family established feudal rule over large amounts of territory 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.

The Nguyễn dynasty remained the formal emperors of Annam and Tonkin within Indochina until World War II. Japan had occupied Indochina with French collaboration in 1940, but as the war seemed increasingly lost, overthrew the French administration in March 1945 and proclaimed independence for its constituent countries. The Empire of Vietnam under the Bảo Đại Emperor was a nominally independent Japanese puppet state during the last months of the war. It ended with the Bảo Đại Emperor's abdication following the surrender of Japan and August Revolution by the anti-colonial Việt Minh in the August 1945. This ended the 143-year rule of the Nguyễn dynasty.^[188]