During the second half of the twentieth century, the political situation in Cambodia became chaotic. King Norodom Sihanouk (later, Prince, then again King), proclaimed Cambodia's independence in 1949 (granted in full in 1953) and ruled the country until March 18, 1970, when he was overthrown by General Lon Nol, who established the Khmer Republic. On April 17, 1975, Khmer Rouge, who under the leadership of Pol Pot combined Khmer nationalism and extreme Communism, came to power and virtually destroyed the Cambodian people, their health, morality, education, physical environment, and culture in the Cambodian genocide.