French Indochina (French: Indochine française) is the designation for the federation of French colonies and protectorates in the Indochina Peninsula that being a part of French colonial empire between 1887 and 1954.
The federation was formed in October 1887, consisted of three Vietnamese regions, Tonkin (North), Annam (Central), and Cochinchina (South), as well as the Kingdom of Cambodia. Laos was added after the Franco-Siamese War in 1893 and Kouang-Tchéou-Wan in 1900. The capital was moved from Saigon to Hanoi in 1902 and again to Da Lat in 1939 until 1945, when it moved back to Hanoi.
In the three protectorates, the French formally left the local rulers in power, who were the Emperors of the Nguyen Dynasty whose their rules limited only on Annam, Kings of Cambodia, and Kings of Luang Prabang, but in fact gathered all powers in their hands, the local rulers acting only as figureheads.