Đàng Trong
In 1887, the colony of French Cochinchina became part of the Union of French Indochina, while remaining separated from the protectorates of Annam and Tonkin. So during the French colonial period, the label "Cochinchina" moved further south, and came to refer exclusively to the southern third of Vietnam. (In Catholic ecclesiastical contexts Cochinchina still related to the older meaning of "Đàng Trong" until 1924 when the three Apostolic Vicariates of Northern, Eastern, and Western Cochinchina were renamed to Apostolic Vicariates of Huế, Qui Nhơn, and Saïgon).