For a few centuries before independence, a part of southern Vietnam was called Cochinchina. It was so named by 16th century Portuguese traders to distinguish its Malay name, Kuchi, from their Indian base in Cochin/Kochi in Kerala.
Portuguese writers called it Cauchy Chyna to differentiate it from Cauchy Coulam (Kochi Kollam/Cochin Quilon). The Malay Kuchi is apparently derived from the Chinese name, Jiāozhǐ (or Giao Chỉ), for the same region. In French, the region was called la colonie de Cochinchine.
Connotations
Indian connection