Cochinchina

Cochinchina (/ˈkoʊtʃɪnˌtʃaɪnə/; Vietnamese: Nam Kỳ; Khmer: កូសាំងស៊ីន, Kausangsin; French: Cochinchine) is a region encompassing the southern third of current Vietnam whose principal city is Saigon or Prey Nokor in Khmer. It was a French colony from 1862 to 1954. The later state of South Vietnam was created in 1954 by combining Cochinchina with southern Annam. In Vietnamese, the region is called Nam Bộ. Historically, it was Gia Định (1779–1832), Nam Kỳ (1834–1945), Nam Bộ (1945–48), Nam phần (1948–56), Nam Việt (1956–75), and later Miền Nam. In French, it was called la colonie de Cochinchine.

In the 17th century, Vietnam was divided between the Trịnh lords to the north and the Nguyễn lords to the south. The northern section was called Tonkin by Europeans, and the southern part called Cochinchina by most Europeans and Quinam by the Dutch. Cochinchina was never a single united administrative unit until the French seized it in the 1850s.

During the French colonial period, the label moved further south, and came to refer exclusively to the southernmost part of Vietnam, controlled by Cambodia in prior centuries, and lying to its southeast. The capital of the French colony of Cochinchina was at Saigon. The two other parts of Vietnam at the time were known as Annam (Central Vietnam) and Tonkin (Northen Vietnam).

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