The prolific Danish Nazi sperm donor who served in the SS and was able to have over 100 children.

A Danish man who served in the SS during World War II and was a prolific sperm donor has been identified as the biological father of more than 15 individuals born in Sweden, Denmark, Germany, and Finland during the 1960s. The revelation came after these individuals underwent DNA testing to trace their ancestry, uncovering that their true parent was Walther Frisch, a staunch Nazi who died in 1992. Frisch, who had never expressed remorse for his wartime activities, may have fathered over 100 children through a fertility program at Stockholm’s prestigious Karolinska Institute. The discovery emerged from a documentary produced by Denmark's public broadcaster DR, titled The Mystery of the Nazi Donor, which investigated Frisch’s life and his potential offspring. Among those affected is Thomas Rasmussen, a Dane who described the shock of learning that his biological father was a former SS officer. Another confirmed child, Mats Rydberg from Sweden, questioned whether they were the result of a Nazi-era eugenics experiment. “How could someone who served in the Waffen-SS become my sperm donor?” Rasmussen asked in the film. Rydberg added, “Heinrich Himmler once stated that every SS officer should have at least four children. Are we the product of such an experiment?” Frisch’s involvement with the Karolinska Institute during the 1960s raises questions about how he was approved as a donor despite his past. At the time, Sweden was a pioneer in hormonal treatments and artificial insemination, attracting many women from northern Europe seeking motherhood. While the exact reason for Frisch’s donations remains unclear, some of his children suspect ideological motives, especially given the presence of other former Nazis connected to the institute. Lars Ove Cassmer, a Swedish doctor who worked at Karolinska in the 1960s, was linked to hormone research during the period when Frisch’s children were conceived. Rasmussen suggested that the Karolinska Institute should investigate why Frisch was chosen so frequently as a donor, considering his age and history. “It would be good if it wasn’t ideological,” he said, adding that the number of known children already suggests there could be far more than 100 descendants. Karolinska declined to comment directly for the documentary but issued a statement condemning the possibility of ideological motivations behind the selection of donors. It called the idea “totally unacceptable” and “deeply unethical.” The hospital noted that its archives contain no information about Frisch and explained that in the 1960s, doctors were allowed to work on private projects, which might explain the lack of records regarding donations or Cassmer’s possible involvement. Frisch lived in Stockholm during the 1960s, where he married and worked as a maître d’hôtel at the city hall and later at an auction house. He had moved from Denmark after serving one year in prison for collaboration with the Nazi regime. Born in 1917 in Viby, a town near Aarhus that has since merged into the larger city, Frisch volunteered for the Waffen-SS in May 1942 at the age of 25. The Waffen-SS, elite military units under the control of the Nazi Party rather than the regular German army, were responsible for numerous atrocities during the war. Frisch’s story highlights the complex legacy of Nazi collaborators and the ethical dilemmas surrounding medical practices in post-war Europe. His case has sparked renewed interest in the historical connections between Nazi ideology and scientific experimentation, particularly in the field of reproductive medicine. As more individuals come forward with their findings, the full extent of Frisch’s influence and the implications of his actions continue to unfold.