In March 1945, King Norodom Sihanouk, with the approval of the Japanese, who had earlier taken over the government, proclaimed Cambodia's independence and set up a government under Premier Son Ngoc Thanh, a leader in the movement for independence. In October, British, Indian, and French troops occupied Phnom Penh, the capital, and sentenced Son Ngoc Thanh to house arrest in Paris. Early in the following year France accorded Cambodia internal autonomy, and finally in the autumn of 1949 granted de jure independence while retaining control of defense, foreign affairs, and internal security.
King Sihanouk left for voluntary exile in Thailand as a dramatization of his country's demands for complete independence. He returned suddenly, on June 20. Amid mounting tension with France, Cambodian army units seized control of all government buildings.
