French Indochina saw the Japanese occupation in 1940 amidst the escalation of World War II. Following Japanese defeat in 1945, the Vietnamese fought French rule in the First Indochina War. On 2 September 1945, Vietnamese revolutionary leader Hồ Chí Minh declared Vietnam's independence from France and therefrom established a provisional communist state. After nine years of war, the Vietnamese declared victory in the decisive battle of Điện Biên Phủ in 1954. The nation was thereafter divided into two rival states, communist North—the Democratic Republic of Vietnam, and anti-communist South—the Republic of Vietnam. Conflicts intensified in the Vietnam War with extensive US intervention in support of South Vietnam from 1965 to 1973. The war ended with North Vietnamese victory in 1975.