No, sorry, that would be Mao Zedong's slaughter of his own people that significantly eclipses the communist takeover and Stalin's leadership in Russia/USSR. Mao has Stalin and the Bolshevik's beaten by a few tens of millions of dead. Second would be Stalin. Third would be Hitler (even subtracting out all 6 million Jews, he's still 3). Fourth is Leopold II. Fifth is Hideki. Sixth is Pasha. Seventh Pol Pot And somewhere around Seventh and Eighth, you have the Bolsheviks.