In the early 20th century, a technology designed for census-taking was transformed into a critical logistical tool for one of history’s darkest periods. IBM’s punched card systems, developed decades earlier for data processing, became intertwined with Nazi Germany’s administration from the regime’s earliest days through the end of the Second World War.
From Census Innovation to Global Business
In the 1880s, Herman Hollerith developed punched cards that encoded population data through perforations, enabling mechanical tabulation. In 1910, Willy Heidinger founded Deutsche Hollerith Maschinen Gesellschaft (Dehomag) as IBM’s German licensee. IBM acquired Dehomag in 1923 and, under Thomas J. Watson’s leadership, rebranded as International Business Machines in 1924.
After Adolf Hitler took power in January 1933, the Nazi regime began mass repression. A census launched in April 1933 aimed to identify Jews, Roma, and other targeted groups. Dehomag offered its services to the Prussian government, and Watson approved increasing IBM’s German capital to 7 million Reichsmarks to expand operations, including building a Berlin factory. Using IBM machines, the census raised the official estimate of Jews in Germany from roughly 500,000 to about two million.
Expansion Across Occupied Europe
As Germany occupied other territories, IBM subsidiaries supported new censuses. According to historical accounts, punch-card systems were used to track populations and manage logistics. IBM operated through a leasing model: machines were not sold but leased, with IBM retaining control over punch-card production and service. Each card design was customized for Nazi administrative needs, including transportation records and concentration camp registrations.
In occupied Poland, IBM New York established Watson Business Machines, which managed railway traffic in the General Government and operated a punch-card printing facility near the Warsaw Ghetto. Reports indicated that this subsidiary communicated through Geneva with IBM’s New York headquarters, and revenues were transferred accordingly.
Lawsuits and Historical Investigation
In 2001, investigative journalist Edwin Black published IBM and the Holocaust, detailing these relationships. The book documented IBM’s dealings through archives, corporate records, and wartime documents, outlining how punch-card systems were used throughout the Nazi administration. IBM criticized aspects of the book but did not request factual corrections.
Legal actions followed. A U.S. federal lawsuit under the Alien Tort Claims Act was filed in 2001, accusing IBM of providing technology that facilitated Nazi operations, but it was withdrawn to avoid delaying payments from a German Holocaust fund. In 2004, a separate case in Switzerland brought by a Roma organization was dismissed in 2006 due to statutes of limitations.
In the 1930s, IBM’s punch-card machines were quietly placed at the heart of a growing dictatorship.
While the world watched Germany’s new regime consolidate power, IBM’s German branch expanded fast, supplying the technology that would catalog millions…👇🧵 pic.twitter.com/ShaOXPydua
— Fascinating True Stories (@FascinatingTrue) October 14, 2025