From 1882 until 1941, Laos, Cambodia, and Vietnam comprised French Indochina, France's richest and most important colony. Forced to relinquish control to the Japanese following their surrender to Germany in 1941, the French returned to Southeast Asia in 1946, determined to regain their profitable possessions. The war in the Pacific gave a strong fillip to anticolonial movements throughout the area, and Indochina was no exception. Shortly after Japan's surrender, Ho Chi Minh – leader of the Vietminh, a broad-based but communist-led resistance movement – proclaimed from Hanoi the existence of a new nation, the Democratic Republic of Vietnam (DRV). Over the next year and a half, however, the French, with the help of the British in the South and the Chinese Nationalists in the North, managed to reestablish themselves firmly in the South and tentatively in the North. In November 1946 a bitter colonial war erupted between the French and the Vietminh, culminating in 1954 with France's defeat at the battle of Dien Bien Phu. A subsequent peace conference at Geneva provided for the temporary division of the country at the seventeenth parallel. The French withdrew from the peninsula but left an anticommunist regime in place in the South – the Republic of Vietnam (RVN) – under Emperor Bao Dai and his prime minister, Ngo Dinh Diem. Within a year Diem had ousted Bao Dai and instituted a presidential system with himself as chief executive. Meanwhile, in the North, Ho consolidated his power as head of the DRV.