The social policies of eugenics in Nazi Germany were composed of various ideas about genetics. The racial ideology of Nazism placed the biological improvement of the German people by selective breeding of "Nordic" or "Aryan" traits at its center. These policies were used to justify the involuntary sterilization and mass murder of those deemed "undesirable".
Eugenics research in Germany before and during the Nazi period was similar to that in the United States, by which it had been heavily inspired. However, its prominence rose sharply under Adolf Hitler's leadership when wealthy Nazi supporters started heavily investing in it. The programs were subsequently shaped to complement Nazi racial policies.
Those targeted for murder under Nazi eugenics policies were largely people living in private and state-operated institutions, identified as "life unworthy of life" (Lebensunwertes Leben). They included people with congenital cognitive and physical disabilities (Erbkranken) – people who were considered to be feeble-minded. In fact being diagnosed with "feeblemindedness" (German: Schwachsinn) was the main label approved in forced sterilization, which included people who were diagnosed by a doctor as, or otherwise seemed to be:
Manic-depressive (now known as bipolar)
Suffering from Cerebral palsy or muscular dystrophy
Homosexual or "transvestites" (which at the time was used to refer to intersex and transgender people, particularly trans women)
Anyone else considered to be idle, insane, and/or weak as per "feeblemindedness"
All of these were targeted for elimination from the chain of heredity. More than 400,000 people were sterilized against their will, while up to 300,000 were murdered under the Aktion T4 euthanasia program. Thousands more also died from complications of the forced surgeries, the majority being women from forced tubal ligations.
In June 1935, Hitler and his cabinet made a list of seven new decrees, in which number 5 was to speed up the investigations of sterilization.
An attempt to relieve the overcrowding of psychiatric hospitals, in fact, played a significant role in Germany's decision to institute compulsory sterilization and, later, the killing of psychiatric patients. [...] Hitler's letter authorizing the program to kill mental patients was dated September 1, 1939, the day German forces invaded Poland. Although the program never officially became law, Hitler guaranteed legal immunity for everyone who took part in it.
In German, the concept of "eugenics" was mostly known under the term of Rassenhygiene or "racial hygiene". The loanword Eugenik was in occasional use, as was its closer loan-translation of Erbpflege. An alternative term was Volksaufartung (approximately "racial improvement").
Relationship with the U.S. eugenics movement
The early German eugenics movement was led by Wilhelm Schallmayer and Alfred Ploetz. Henry Friedlander wrote that although the German and American eugenics movements were similar, the German movement was more centralized and did not contain as many diverse ideas as the American movement. Unlike the American movement, one publication and one society, the German Society for Racial Hygiene, represented all eugenicists.
Edwin Black wrote that after the eugenics movement was well established in the United States, it was spread to Germany. California eugenicists began producing literature promoting eugenics and sterilization and sending it overseas to German scientists and medical professionals. By 1933, California had subjected more people to forceful sterilization than all other U.S. states combined. The forced sterilization program engineered by the Nazis was partly inspired by California's.
In 1927, the Kaiser Wilhelm Institute for Anthropology (KWIA), an organization which concentrated on physical and social anthropology as well as human genetics, was founded in Berlin with significant financial support from the American philanthropic group the Rockefeller Foundation. German professor of medicine, anthropology and eugenics Eugen Fischer was the director of this organization, a man whose work helped provide the scientific basis for the Nazis' eugenics policies. The Rockefeller Foundation even funded some of the research conducted by Josef Mengele before he went to Auschwitz.
Upon returning from Germany in 1934, where more than 5,000 people per month were being forcibly sterilized, the California eugenics leader C. M. Goethe bragged to a colleague:
You will be interested to know that your work has played a powerful part in shaping the opinions of the group of intellectuals who are behind Hitler in this epoch-making program. Everywhere I sensed that their opinions have been tremendously stimulated by American thought... I want you, my dear friend, to carry this thought with you for the rest of your life, that you have really jolted into action a great government of 60 million people.
Eugenics researcher Harry H. Laughlin often bragged that his Model Eugenic Sterilization laws had been implemented in the 1935 Nuremberg racial hygiene laws. In 1936, Laughlin was invited to an award ceremony at Heidelberg University in Germany (scheduled on the anniversary of Hitler's 1934 purge of Jews from the Heidelberg faculty), to receive an honorary doctorate for his work on the "science of racial cleansing". Due to financial limitations, Laughlin was unable to attend the ceremony and had to pick it up from the Rockefeller Institute. Afterwards, he proudly shared the award with his colleagues, remarking that he felt that it symbolized the "common understanding of German and American scientists of the nature of eugenics."