The number of deaths during those three months is so huge that it accounts for more than a quarter of the known Holocaust victims. Stone said he "couldn't believe his eyes" when he uncovered the results and looked back on previous research to check that he had not made a mistake.
"To my surprise, historians have completely avoided quantitative approaches for examining this period. But the graphs show with chilling immediacy the bloodlust of the Nazi programme to obliterate the Jewish people in as short a time as possible," he said. "The subsequent rapid plunge in the death rate in November and December 1942 simply reflects that there were very few Jewish victims left alive to murder. It highlights the frenzied killing the Nazis planned for the Final Solution to the Jewish Question and their ability and eagerness to carry it out."
The new estimates are based on work by Yitzhak Arad, an Israeli historian who compiled data on 480 train deportations from 393 Polish towns and ghettos during the German offensive. Most of the victims of the Nazi mission to wipe out Polish Jews were gassed to death and their bodies buried in pits. The corpses were later exhumed, cremated and their bones ground up to hide the huge numbers.
The new murder rate would mean the Rwandan genocide, in which 800,000 people were murdered in just 100 days, was not the most intense of the 20th century.
Commenting on the findings, published in the journal Science Advances, Holocaust expert Professor Sir Richard J. Evans of Cambridge University, said that in August 1942 a more orderly SS leadership stepped in. "It is not surprising therefore that the killing rate accelerated as it became more efficient," he said.