French Indochina officially known as the Indochinese Union and after 1947 as the Indochinese Federation, was a grouping of French colonial territories in Southeast Asia until its demise in 1954. It comprised Cambodia, Laos (from 1899), the Chinese territory of Guangzhouwan (from 1898 until 1945), and the Vietnamese regions of Tonkin in the north, Annam in the center, and Cochinchina in the south. The capital for most of its history (1902–45) was Hanoi; Saigon was the capital from 1887 to 1902 and again from 1945 to 1954.

Source: Wikipedia