Nazi Germany: Census and Data Infrastructure

Hollerith Tabulating Machines and Dehomag

Herman Hollerith invented punch card tabulator for 1890 US Census. IBM (formerly CTR) commercialized globally. Dehomag (Deutsche Hollerith-Maschinen Gesellschaft), IBM’s German subsidiary, customized for German needs — custom-designed cards with columns for religion, nationality, mother tongue.

Edwin Black, IBM and the Holocaust (2001): documents how Dehomag’s technology enabled the Reich to cross-reference census data, identifying Jews and mixed-ancestry individuals. IBM maintained involvement through Geneva office. Leased machines and sold cards throughout the war. Machines appeared at concentration camps for tracking prisoner labor and mortality.

German Censuses

• 1925 (Weimar): routine census
• June 16, 1933: census months after Hitler took power. Included questions on religion and ancestry. Processed on Hollerith machines by Dehomag.
• 1939 supplemental census: required detailed racial ancestry declarations.

Each person became a punch card; each card could be sorted, counted, matched to an address.

The Netherlands — Population Registry

The Bevolkingsregister (population registry), maintained by municipalities since 1850, recorded every resident’s religion, address, and family relationships.

When Germany occupied the Netherlands (May 1940), registry was intact and accessible. Result: ~73-75% of Dutch Jews (~102,000 of ~140,000) murdered — highest proportion in Western Europe. France, with less centralized records: ~25% (~76,000 of ~300,000).

Jacobus Lambertus Lentz, head of Dutch Population Registry, enhanced the system under occupation, creating near-forgery-proof identity card.

Resistance fighters attacked Amsterdam population registry March 1943.

Key References

• Edwin Black, IBM and the Holocaust (2001)
• Gotz Aly and Karl Heinz Roth, The Nazi Census (2004)
• Pim Griffioen and Ron Zeller on Dutch deportation rates