By resolution of the city council on February 23, 1967, a street in the Bierstadt district was named after the doctor and university professor Gerhardt Katsch. Gerhardt Katsch was born in Berlin on May 14, 1887 as the son of the playwright and painter Hermann Katsch and his wife, the dramaturge Elisabeth Katsch, née Beutner. Katsch attended secondary school and the French Gymnasium in Berlin from 1893 to 1905. He then studied biology, physics and philosophy in Paris.

From 1906, Katsch studied medicine in Marburg and Berlin and was awarded his doctorate in Berlin in 1912. In the same year, he became an assistant doctor at the Hamburg-Altona Municipal Hospital, where he was appointed senior physician in 1914. After the outbreak of the First World War, Katsch did military service as a reserve battalion doctor from August 1914 to January 1917 and from August to November 1918. In 1917, Katsch was granted leave from the army at the instigation of his academic teacher Gustav von Bergmann and habilitated at the University of Marburg.
After the end of the First World War, Katsch remained in Marburg as a senior physician with his mentor von Bergmann and moved with him to the University Hospital in Frankfurt am Main in 1920, where he was appointed associate professor. In 1926, Katsch was appointed Chief Physician at the Medical Clinic of the Heilig-Geist-Hospital in Frankfurt am Main and in 1928, he was appointed Director of the Medical Clinic in Greifswald and Professor of Internal Medicine at the University of Greifswald.

Katsch's work and research focused on diabetes mellitus. In order to improve research into and treatment of diabetes, Katsch helped to establish the "Arndt Foundation Garz Diabetic Home" on the island of Rügen. In 1937, the physician wrote the "Garz Theses", a treatment method for diabetes, and initiated a paradigm shift in the characterization of the disease. Katsch considered diabetes to be a treatable disease.

Katsch based his treatment on a four-pillar system: diet, insulin, work and community life. Katsch tried to put this concept into practice in his diabetic home on the island of Rügen.

After the National Socialists came to power in 1933, medical researchers discussed whether diabetics should be included in the National Socialist hereditary health programme and sterilized. As part of this debate, Katsch repeated his "Garz Theses" and argued that although diabetics were ill, the disease was treatable. He rejected sterilization in principle, but did not rule it out in individual cases.

Various speeches and lectures show that, despite his reservations about the general sterilization of diabetics, Katsch argued within the paradigms of Nazi racial hygiene and the National Socialists' concept of public health. In the discussion about the inclusion of diabetics in forced sterilization processes, Katsch finally prevailed. Those affected were not generally covered by the "Law for the Prevention of Hereditarily Diseased Offspring" of July 14, 1933.

Katsch became a party candidate for the NSDAP in 1937 and received his party membership card in 1943. As a member of the "Stahlhelm - Bund der Frontsoldaten", Katsch was also transferred to the SA in 1933/34, where he held the rank of Oberscharführer. Katsch probably also held the position of Sturmbannarzt in the SA. Gerhardt Katsch was also a supporting member of the SS and the National Socialist Flying Corps. The supporting members of the SS formed a sub-organization of the SS, which non-NSDAP members could also join and which served to collect donations for the establishment and expansion of the SS. No formal service in the SS was associated with the financial contributions, which were usually paid monthly. Memberships in the National Socialist People's Welfare Organization, the Reich Air Protection League and the Reich Colonial League are also documented.

In the immediate post-war period, probably in 1946, Katsch addressed his relationship to the NSDAP and the Nazi regime in a written statement. In this statement, he emphasized that his adherence to a Jewish assistant, the physician Alfred Lublin, had led to conflicts with the party. Katsch also reported attempts at denunciation. In 1935, he was asked to submit a certificate of descent at short notice. In addition, a request from the Reich Minister for Science, Education and National Education from October 1938 to submit his wife's proof of parentage to complete his personal file has been preserved. Katsch then submitted his wife's ancestry certificate. Party correspondence on Katsch also contains evidence that he was in fact subject to attacks from colleagues because of his alleged "non-Aryan" ancestry. In 1944, Paul Rostock, the Commissioner for Medical Science and Research of the Nazi General Commissioner for the Medical and Health Service, made enquiries about the internist from several of the doctor's colleagues and the Nazi Lecturers' Association at the University of Greifswald. The reason for this was the intention to entrust Katsch with a professorship at a larger university. At the end of March 1944, Gunther Schultze, the Nazi lecturer leader in Greifswald, confirmed in response to this inquiry that there were no reservations about Katsch.

Attacks or professional disadvantages could not be proven. Accordingly, Katsch was also considered for a professorship at a larger university in 1944. At the same time, it remains unclear whether the internal university attacks against Katsch were also a reason for the large number of his memberships in Nazi organizations.

It also remains questionable whether Katsch's alleged support for his assistant Lublin was actually the cause of hostility from the faculty of the University of Greifswald. In any case, there is no evidence of active support for Lublin in contemporary documents.

The beginning of the Second World War also influenced Katsch's medical activities. In 1940, he suggested to his dean that teaching should be moved to a large wartime hospital. The suggestion was not followed.

Katsch himself became a consultant internist for the medical service in military district II and was responsible for managing the Greifswald reserve hospitals. As a military doctor, Katsch was deployed close to the front in the Balkans and Ukraine several times during the war. After the invasion of the Soviet Union in June 1941, Katsch was assigned the medical supervision and care of the Stalag II C prisoner-of-war camp. As a consultant internist, Katsch also worked closely with the Army Medical Inspection, in particular with the Chief Consultant Internist at the Army Medical Inspection, Kurt Gutzeit. In the course of this work, Katsch was also involved in military research projects and took part in conferences such as the "Work Conference East" organized by the Army Medical Inspection in March 1943. At this conference, Karl Gebhardt and his colleague Fritz Fischer presented the results of their experiments with sulfonamide on intentionally injured inmates of the Ravensbrück concentration camp. Katsch was thus informed about criminal human experiments in the German concentration camp system by this time at the latest.

At the Greifswald Medical Clinic, Katsch and his senior physician Martin Gulzow carried out so-called feeding experiments on Soviet prisoners of war from the POW camp assigned to him from November 1941. The experiments were intended to investigate metabolic disorders that occurred as a result of malnutrition.

These experiments were carried out on 16 prisoners of war. Three prisoners of war died, thirteen recovered. After their treatment, several of these recovered prisoners of war were used as forced laborers in the Greifswald clinic and in agriculture. For Gerhardt Katsch, these experiments were not only about saving human lives, but also about generating nutritional and physiological knowledge. They were of indirect interest to the Wehrmacht and military medicine and were considered relevant to the war economy.

When the Red Army advanced on Greifswald at the end of the war, Katsch was part of a seven-man German surrender delegation that negotiated the surrender of the city of Greifswald without a fight in Anklam. Katsch described the events in a report he wrote himself after 1945. It is unclear exactly what role he played in the surrender of the town. In any case, it was by no means unusual for a high-ranking medical officer to be involved in one of the numerous decentralized surrender negotiations of Wehrmacht units and units in the last days of the "Third Reich". The central descriptions of the post-war period, in particular the drastic description of the supposed danger to his own person, were largely written by Katsch himself. Photos document his presence at a meeting with the Red Army, but it is no longer possible to reconstruct exactly what role Katsch played in these negotiations.

What is certain is that Katsch himself repeatedly brought up the subject of his involvement in Greifswald's surrender and was finally made an honorary citizen of Greifswald in 1952. In the German Democratic Republic, Katsch was able to continue his research and received intensive support. He wrote numerous studies, supervised several hundred dissertations and habilitations, received additional salaries and expense allowances and traveled abroad to give lectures and attend congresses. In 1952, he was awarded the National Prize of the GDR, in 1953 Katsch became a full member of the German Academy of Sciences, and in 1954 he was appointed Rector of the University of Greifswald. He held this office until 1957. In 1955, he was admitted to the Leopoldina.

Katsch chaired the German Congress of Internists (opens in a new tab) in Wiesbaden several times and in 1953 became chairman of the German Society of Internal Medicine, which acted as an all-German association until 1959. Katsch also received numerous honors. In 1951, he was awarded the honorary title of "Meritorious Doctor of the People" in the GDR. In 1953, the University of Greifswald made him an honorary senator. In 1956, he was awarded the title "Outstanding Scientist of the People". A year later, the University of Greifswald awarded him an honorary doctorate and the university's chain of honor. He died in Greifswald on March 7, 1961.

Gerhardt Katsch's role during the "Third Reich" has been the subject of controversial debate since the mid-1990s. As early as 1994, there was a demonstration during the Diabetics' Day in Berlin against the continued awarding of the Gerhardt Katsch Medal, which was created in 1979, by the German Diabetes Society. In 2001, the diabetologist Michael Berger refused to accept the Gerhardt Katsch Medal. Berger not only criticized Katsch's role in the "Third Reich" but also called for a more realistic assessment of Katsch's contribution to German diabetes research. Berger's criticism led to the convening of a historical commission by the German Diabetes Society.
The commission, which was made up exclusively of doctors, primarily assessed Katsch's medical achievements. On the question of his relationship to National Socialism and its health policy, however, the report followed Katsch's statements from the post-war period. The expert opinion initially had no direct consequences. The Gerhard Katsch Medal was renamed the Medal of Honor of the German Diabetes Society when it was awarded in 2023, after more recent medical history studies suggested that it could no longer be ruled out that Katsch had acted unethically during the National Socialist era, as the German Diabetes Society stated.

The Historical Expert Commission appointed by the City Council in 2020 to review traffic areas, buildings and facilities named after people in the state capital of Wiesbaden recommended renaming Gerhardt-Katsch-Straße because of Katsch's memberships in various National Socialist organizations (NSDAP, SA, Demanding Member of the SS, Supporting Member of the NSFK, NSV, RKB, RLSB). He was also a functionary of the SA as Oberscharführer and Sturmbannarzt and thus actively supported the National Socialist state. Before 1933, he was a member of the "Stahlhelm - Bund der Frontsoldaten", a nationalist group. Katsch publicly articulated the National Socialist ideology in writings and speeches by advocating the health policy and racial hygiene of the Nazi regime. He thus made a public commitment to National Socialism.

In June 1941, Katsch was also entrusted with the medical supervision and care of the Stalag II C prisoner of war camp. In the course of this work, he carried out so-called feeding experiments on 16 Soviet prisoners of war from November 1941. For these reasons, Katsch was involved in the deliberate harming of other people between 1933 and 1945.