French Cochinchina (sometimes spelled Cochin-China; French: Cochinchine française; Vietnamese: Xứ thuộc địa Nam Kỳ, chữ Hán: 處屬地南圻) was a colony of French Indochina from 1862 to 1949, encompassing the Mekong Delta and adjacent provinces in what is now the southern region of Vietnam, with its administrative capital in Saigon (present-day Ho Chi Minh City). In the face of recurring peasant unrest, and of growing political agitation in Saigon, the French operated a plantation economy whose primary strategic product was rubber.
After the end of the Japanese occupation (1941–1945) and the expulsion from Saigon of the Communist-led, nationalist Viet Minh in 1946, the territory was reorganized by the French as the Autonomous Republic of Cochinchina, a decision that helped trigger the First Indochina War. In a further move to deny the claims of the Democratic Republic of Vietnam declared in Hanoi by the Viet Minh, in June 1949 Cochinchina was united with the protectorates of Annam and Tonkin under their former de jure emperor Bảo Đại as the State of Vietnam within the French Union.