Cochinchina

Cochin China (or Cochinchina) was the southernmost part of Vietnam beside Kampuchea. Originally called Jiaozhi (交阯 or 交趾) by its Chinese rulers, Cochin was named after the unknown realm south of the Five Mountain Ranges (五嶺) in the legendary time of Sanhuangwudi. Its name may be phonetic, but the characters also have the meaning of "crossed bases of hills" and "crossed toes." Locally, it is called Nam Bộ (南圻), meaning "Southern Boundary."

In 111 BC, under the reign of Wudi of Han China, the Jiaozhi Prefecture (交趾郡) was established, among two other prefectures in other parts of Vietnam: Jiuzhen (九真郡) and Ri'nan (日南郡). In 939, Ngô Quyền (吳權) self-proclaimed to be the King of the Cochin Kingdom and started the Ngo Dynasty.

During the French Occupation, it was called Cochinchine in French, and capital was at Saigon. The two other parts of Vietnam at the time were Annam and Tonkin.