French Cochinchina (sometimes spelled Cochin-China; French: Cochinchine française; Vietnamese: Xứ thuộc địa Nam Kỳ, Hán tự: 處屬地南圻) was a colony of French Indochina, encompassing the whole region of Lower Cochinchina or Southern Vietnam from 1862 to 1946. The French operated a plantation economy whose primary strategic product was rubber. Nam Kỳ originated from the reign of Minh Mạng of the Nguyễn dynasty, but became a name associated with the French colonial period and so Vietnamese, especially nationalists, prefer the term Nam Phần to refer to Southern Vietnam.