most killed by a regime;
Communists and Stalin: It is calculated that the Communist regime, 1917-1987, murdered about 62 million people, around 55 million of them citizens.
but, the number 1 in the shortest amount of time is;
Mao Tse Tung: During the years 1958 and 1959, China experienced what was hailed by Marxists as the "Great Leap Forward." During this time, Mao Tse Tung's regime was directly responsible for between 30 and 40 million deaths.
By comparison, the Holocaust saw 9-11 million people dead a result of Hitler and the Nazis.
most killed in a day;
The Atomic Bomb on Hiroshima killed 80,000 which is probably the highest civilian death toll in one day
most killed by one person;
A 16th century Hungarian countess named Elizebeth Bathory (August 7, 1560 - August 24, 1614) is said to have killed over 600 young women. She was convicted of only 80.
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