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 a 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, 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 as well as Tonkin. They later cancelled treaties with France and were the Empire of Vietnam for a short time until 25 August 1945.

The French conquest of Vietnam1 (1858–1885) was a series of military expeditions that pitted the Second French Empire, later the French Third Republic, against the Vietnamese empire of Đại Nam in the mid-late 19th century. Its end and results were victories for the French as they defeated the Vietnamese and their Chinese allies in 1885, the incorporation of Vietnam, Laos, and Cambodia, and finally established French rules over constituent territories of French Indochina over Mainland Southeast Asia in 1887.