During World War II, after the fall of France and establishment of Vichy France, the French had lost practical control in French Indochina to the Japanese, but Japan stayed in the background while giving the Vichy French administrators nominal control. This changed on 9 March 1945 when Japan officially took over. To gain the support of the Vietnamese people, Imperial Japan declared it would return sovereignty to Vietnam. Emperor Bảo Đại declared the Treaty of Huế made with France in 1884 void. Trần Trọng Kim, a renowned historian and scholar, was chosen to lead the government as prime minister.