The researcher, originally from Warsaw, was not alone in this choice of words, which seems so appalling from a modern-day perspective. Berlin-based serologist Fritz Schiff, for example, insisted in the academic journal Jüdische Familienforschung (Jewish Genealogical Research) that differences in the blood types of various Jewish groups could be seen "as an 'convergence' to become more like the respective 'host people.'"
Ludwik and Hanna Hirszfeld had begun spreading dubious theories in the 1920s. And, as Spörri writes: "The idea of 'pure blood' first expressed by the Hirszfelds held on tenaciously and was never challenged, despite new findings."
Nearly all researchers of the period shared this obsessive preoccupation with the idea of blood purity. Years before the Nazis seized power, both Jewish and non-Jewish blood-group researchers were searching for racial characteristics and signs of racial mixing in the blood, assuming the existence of such things as a matter of course.
In her book, Spörri illuminates for the first time a community of academics whose members, by today's standards, seem impossibly mismatched, and whose work has largely faded from public consciousness. On the one hand, there were liberally minded scientists of Jewish ancestry, such as Hirszfeld, Schiff and Landsteiner. On the other side was a more reactionary group who were followers of Hamburg anthropologist Otto Reche, who founded the German Society for Blood Group Research in 1926.
It seems astonishing from a present-day point of view, but these extremely different players in the blood research scene were very often in agreement. In 1929, for example, Landsteiner, who had by this time emigrated to New York, took the time during a visit back to Germany to meet with the obscure race researcher Reche. In a letter to a colleague, the racist scientist who later became an admirer of Hitler, vacillated between mistrust and admiration of Landsteiner: "He is a tall, slim, good-looking man with a proud fencing scar on his left cheek; his racial type is not very apparent … he has produced a number of very good ideas."
Hitler, too, had an ardent interest in the subject, although he obtained his information from crude sources. His inspiration for the "Law for the Protection of German Blood and German Honor," passed in 1935 as one of the Nuremberg Laws, was an unsavory 1917 pulp novel called "The Sin against the Blood."
Early Applications of Blood Type Research
On the whole, though, instead of causing a setback for medical research in Germany, this erroneous belief in the "purity" of blood advanced it to a certain extent. German scientists were leaders in the field when it came to research into hereditary blood characteristics. The first time a blood group report was submitted in court as evidence in a paternity case was in Germany, in 1924.
German forensic scientists in the early 20th century also achieved the great feat of convicting a serial killer on the strength of a blood test. Ludwig Tessnow, a journeyman carpenter, was suspected of having murdered four children. His sullied clothing was taken as evidence of his guilt.
Tessnow, hard-pressed and unaware of the possibilities available to modern medicine, claimed the spots in question were simply from wood stain. But experts were able to identify the traces as human blood using a blood precipitation test, leading to Tessnow's execution in 1904.