Oscar Gross grew up in Mainz as the son of the merchant Heinrich Gross and his wife Rosa, née Ettlinger. He attended the Grand Ducal Gymnasium in Mainz. After graduating from high school in 1900, he took up medical studies in Freiburg im Breisgau. He also studied in Leipzig, Munich, and Berlin.
Gross passed the state examination in Freiburg on January 24, 1905 and was awarded his doctorate the same year under Heinrich Kiliani (1855-1945), the professor of chemistry at the medical faculty, with a thesis on the excretion of alkalis and alkaline earths in the urine.1 He completed his traineeship at the medical clinic in Strasbourg under Ludolf von Krehl (1861-1937) and at the eye clinic of the university in Würzburg under Carl von Hess (1863-1923).
Work in Greifswald
After having received his license to practice medicine, Gross took up a position as an intern at the Medical Clinic of the University of Greifswald, headed by Oskar Minkowski (1858-1931), on October 1, 1906. He was appointed senior physician in August 1909. He habilitated four months later, on December 4, 1909. Gross did research on metabolic diseases, especially cholesterol and digestive enzymes.2 Gross became a renowned expert in the field of clinical pancreas research after he had been encouraged and influenced by Minkowski, who had moved to Breslau as clinic director in 1909.3 He was awarded the title "professor" in recognition of his scientific achievements.
Minkowski was succeeded as clinic director in Greifswald by Paul Morawitz (1879-1936). When Morawitz became a military doctor during World War I, Gross took over the management of the clinic for internal medicine and polyclinic, as well as his teaching duties on an interim basis. After his return, Morawitz campaigned for Oskar Gross to be promoted to the rank and title of "associate professor".5
After Morawitz accepted a call to Würzburg, Gross took over as senior physician in charge of the polyclinic as of October 1, 1922. Hermann Straub (1882-1938), who had been appointed from Halle, became head of the medical clinic the same year.
Move to Saarbrücken
Gross moved to the Saarland in 1923 and became chief physician of the medical department at the Bürgerhospital (citizen's hospital) in Saarbrücken.6 He did not want to give up his position in Greifswald completely "in view of the special political conditions in the Saar region"7 and took leave of absence. The "Saar region" had been placed under the administrative sovereignty of the League of Nations for 15 years after the Treaty of Versailles came into force,
National Socialist Repressions and Emigration to the USA
Gross was a Protestant, but was persecuted as a Jew by the National Socialists. He was forcibly dismissed from his position at the municipal hospital in Saarbrücken in 1936; Hans Dietlen (1879-1955) was appointed as his successor. Gross, who had been awarded the "Grossherzogliches Hessisches Militärsanitätskreuz am Kriegsbande" (Grand Ducal Hessian Military Medical Cross on the War Ribbon) (GHSK) in 1918, tried to enforce his recognition as a "front-line fighter". He was, however, unsuccessful and was denied any salary or pension entitlements.
Gross then went to Frankfurt am Main and continued his medical work with his own practice at Arndtstrasse 25 in order to be able to make a living.8 Due to increasing repression, including the withdrawal of his license to practice, he finally decided to emigrate and traveled to London in 1939, shortly before the start of the war. Here Gross found refuge with the support of the British Society for the Protection of Science and Learning. He had influential advocates in Siegfried Thannhauser (1885-1962) and Ferdinand Sauerbruch (1875-1951).9
Gross then emigrated to the U.S. in 1940 and settled in Elmhurst, New York. He was granted American citizenship in 1945. His wife Anni, née Bell, and the two youngest of their three children, Karin and Axel, joined him from Germany in 1947. The eldest son, Wolfgang, emigrated to Argentina.10
Gross obtained his U.S. license to practice medicine and set up practice at 1239 Madison Avenue in New York.11 He remained in New York until his death in 1967.
In addition to his longstanding DGIM membership, Gross was a member of the German Society for Circulatory Research, among others, from 1929-1937. In the USA, he later became a member of the Medical Society of the County of New York and the Medical Society of the State of New York in the USA.
Street Renamed in Saarbrücken
The city of Saarbrücken decided to rename the Hans-Dietlen-Weg to "Oscar-Gross-Weg" on 9 January 2019. Dietlen had been one of those doctors who were jointly responsible for the forced sterilization policy of the National Socialists. 12