As the Third Reich embarked upon its plan of conquest and genocide, it faced a cross-tabulation and organisational challenge so monumental, it called for a computer. Only after Jews were identified - a massive and complex task that Hitler wanted done immediately - could they be targeted for efficient asset confiscation, ghettoisation, deportation, enslaved labour, and, ultimately, annihilation.
Of course, in the 1930s no computer existed. But IBM's Hollerith punch-card technology did. Only with IBM's technological assistance was Hitler able to achieve the staggering numbers of the Holocaust.
Edwin Black has now uncovered one of the last great mysteries of Germany's war against the Jews - how did Hitler get the names?