The end of the Vietman War saw the rise of the Khmer Rouge in 1975 which caused a closing of the Cambodian border and a systematic reorganization of Cambodian society. Everyone was sent from the towns and cities to the countryside where they were forced to labor endlessly in the fields and the intelligentsia were brutally exterminated. Torture, terror, and death became routine. Almost two million people ( a quarter of the population) were killed.