People from the Rhine Province

Josef, Baron von Mering (28 February 1849, in Cologne – 5 January 1908, at Halle an der Saale, Germany) was a German physician.
Working at the University of Strasbourg, Mering was the first person to discover (in conjunction with Oskar Minkowski) that one of the pancreatic functions is the production of insulin, a hormone which controls blood sugar levels.
Mering was curious about the pancreas, a comma shaped organ, situated between the stomach and the small intestine. In an effort to discover its function, he removed the organ from a dog. The dog was then noticed frequently urinating on the floor, although it was house trained. Mering realised that this was a symptom of diabetes and tested the urine, which was found to be high in sugar, confirming his suspicion.
Josef von Mering helped to discover barbiturates, a class of sedative drugs used for insomnia, epilepsy, anxiety, and anesthesia. In 1903, he published observations that barbital (then known as diethyl-barbituric acid) has sedative properties in humans. In 1904, he helped to launch barbital under the brand name Veronal. Veronal was the first commercially available barbiturate sedative in any country. Von Mering collaborated with the chemist Emil Fischer, who was also involved in the discovery of barbital.

Ludwig Pastor, later Ludwig von Pastor, Freiherr von Campersfelden (31 January 1854 – 30 September 1928), was a German historian and a diplomat for Austria. He became one of the most important Roman Catholic historians of his time and is most notable for his History of the Popes. He was raised to the nobility by the Emperor Franz Joseph I in 1908. He was nominated for the Nobel Prize in Literature six times.

Hugo Junkers (3 February 1859 – 3 February 1935) was a German aircraft engineer and aircraft designer who pioneered the design of all-metal airplanes and flying wings. His company, Junkers Flugzeug- und Motorenwerke AG (Junkers Aircraft and Motor Works), was one of the mainstays of the German aircraft industry in the years between World War I and World War II. His multi-engined, all-metal passenger- and freight planes helped establish airlines in Germany and around the world.
In addition to aircraft, Junkers also built both diesel and petrol engines and held various thermodynamic and metallurgical patents. He was also one of the main sponsors of the Bauhaus movement and facilitated the move of the Bauhaus from Weimar to Dessau (where his factory was situated) in 1925.
Amongst the highlights of his career were the Junkers J 1 of 1915, the world's first practical all-metal aircraft, incorporating a cantilever wing design with virtually no external bracing, the Junkers F 13 of 1919 (the world's first all-metal passenger aircraft), the Junkers W 33 (which made the first successful heavier-than-air east-to-west crossing of the Atlantic Ocean), the Junkers G.38 "flying wing", and the Junkers Ju 52, affectionately nicknamed "Tante Ju", one of the most famous airliners of the 1930s.
When the Nazis came into power in 1933, they requested Junkers and his businesses aid in the German re-armament. When Junkers declined, the Nazis placed him under house arrest in 1934 and eventually seized control of his patents and company. He died the following year. Under Nazi control, his company produced some of the most successful German warplanes of the Second World War.

Werner Wilhelm Jaeger (30 July 1888 – 19 October 1961) was a German-American classicist.

Wolfgang Walter Arnulf Abendroth (2 May 1906 – 15 September 1985) was a German socialist, jurist, and political scientist. He was born in Elberfeld, now a part of Wuppertal in North Rhine-Westphalia. Abendroth was a radical social democrat and an important contributor to the constitutional foundation of post-World War II West Germany. In 1943 he was forcibly drafted into one of the 999th Division's "probation units" and while stationed in Greece he deserted to the Greek People's Liberation Army (ELAS). After the war he briefly held a Law professorship in East Germany. However, in 1948 he left for West Germany with his family, refusing to disassociate himself from the Social Democratic Party and join the, overwhelmingly stalinist, Socialist Unity Party of Germany (SED) which in 1949 became the ruling party of East Germany. In 1950 he was appointed professor of Political Science at Marburg and also served as a senior judge in the state court of Hesse. In 1961 he was expelled from the Social Demoractic Party for refusing to disassociate himself from the Socialist German Student Union (SDS). Due to his socialist principles and politics Abendroth was for many years after the end of the war under surveillance by West Germany's Intelligence services. First, by the CIA-affiliated, anti-communist, Gehlen Organisation and later, after 1956, by the German Federal Intelligence Service (BND) both of which were led by Reinhard Gehlen, a prominent Nazi before and during World War II.

Oswald Ludwig Pohl (German: [ˈɔsvalt ˈpoːl] ; 30 June 1892 – 7 June 1951) was a German SS functionary during the Nazi era. As the head of the SS Main Economic and Administrative Office and the head administrator of the Nazi concentration camps, he was a key figure in the Final Solution, the genocide of the European Jews. After the war, Pohl went into hiding; he was apprehended in 1946. Pohl stood trial in 1947, was convicted of crimes against humanity, and sentenced to death. After repeatedly appealing his case, he was executed by hanging in 1951.

Ernst Ferdinand Sauerbruch (German: [ˈzaʊ.ɐˌbʁʊx]; 3 July 1875 – 2 July 1951) was a German surgeon. His major work was on the use of negative-pressure chambers for surgery.