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governments have murdered probably around 174 million people during the 20th Century. Most of this killing, perhaps around 110 million people, is due to communist governments, especially the USSR under Lenin and Stalin and their successors (62 million murdered), and China under Mao Tse-tung (35 million). Some other totalitarian or authoritarian governments are also largely responsible for this toll, particularly Hitler's Germany (21 million murdered) and Chiang Kai-chek's Nationalist government of China (about 10 million). Other governments that have murdered lesser millions include Khmer Rouge Cambodia, Japan, North Korea, Mexico, Pakistan, Poland, Russia, Turkey, Vietnam, and Tito's Yugoslavia.
"Fundamentally, genocide is a product of the type of government a country has. There is a high correlation between the degree of democratic freedom a people enjoy and the likelihood that the government will commit democide. Modern democratic governments have committed virtually no domestic genocide. Those governments that commit the most genocide have been totalitarian governments, while those that committed lesser genocide have been partially or wholly authoritarian and dictatorial."
Genocide:Meaning and Definition