Josef Mengele (; 16 March 19117 February 1979), often dubbed the "Angel of Death" (), was a German military officer and physician during World War II at the Soviet front and then at Auschwitz during the Holocaust. He conducted research and experiments on prisoners at the Auschwitz II-Birkenau concentration camp, where he was a member of the team of doctors who selected victims to be murdered in the gas chambers.

Before the war, Mengele received doctorates in anthropology and medicine, and he began a career as a researcher. He joined the Nazi Party in 1937 and the SS in 1938. He was assigned as a battalion medical officer at the start of World War II, then transferred to the Nazi concentration camps service in early 1943. He was assigned to Auschwitz, where he saw the opportunity to conduct genetic research on human subjects. With Red Army troops sweeping through German-occupied Poland, Mengele was transferred away from Auschwitz to the Gross-Rosen concentration camp on 17 January 1945, ten days before the arrival of the Soviet forces at Auschwitz.

After the war, Mengele fled to Argentina in July 1949, assisted by a network of former SS members. He initially lived in and around Buenos Aires, but fled to Paraguay in 1959 and later Brazil in 1960, all while being sought by West Germany, Israel, and Nazi hunters such as Simon Wiesenthal, who wanted to bring him to trial. Mengele eluded capture despite extradition requests by the West German government and clandestine operations by the Israeli intelligence agency Mossad. He drowned in 1979 after suffering a stroke while swimming off the coast of Bertioga, and was buried under the false name of Wolfgang Gerhard. His remains were disinterred and positively identified by forensic examination in 1985 and DNA analysis in 1992.

Early life Mengele was born into a Catholic family in Günzburg, Bavaria, on 16 March 1911, the eldest of three sons of Karl and Walburga (née Hupfauer) Mengele. His younger brothers were Karl Jr. and Alois. Their father was the founder of the Karl Mengele & Sons company (later renamed ), which produced farming machinery. In 1915, the company expanded, and switched to producing military equipment such as specialized wagons for military transport and parts for deploying naval mines. Karl joined the Nazi Party in 1933 and the SS in 1935, primarily as a way to advance his career in local politics. He served as a district economic advisor, and was found during denazification proceedings after World War II to have not been a committed Nazi.

Mengele was successful at school and developed an interest in music, art, and skiing. In 1924, he joined the , a right-wing youth group, and remained a member until 1930, serving as leader of the local chapter from 1927. He completed secondary school in April 1930 and went on to study medicine at the Ludwig-Maximilians-Universität München. After two semesters, he switched to the University of Bonn, where he took his medical preliminary examination. In 1931, he joined , a paramilitary organization that was absorbed into the Nazi ('Storm Detachment'; SA) in 1934. He spent part of 1933 studying at the University of Vienna, and earned his PhD in anthropology from the Ludwig-Maximilians-Universität München in 1935, studying for four years under Theodor Mollison, a physical anthropologist and proponent of the pseudoscience of scientific racism. Mengele's dissertation, titled Rassenmorphologische Untersuchung des vorderen Unterkieferabschnittes bei vier rassischen Gruppen ("Racial morphological study of the anterior segment of the mandible in four racial groups"), attempted to prove that measurements of the lower jaw could be used to determine race.

In January 1937, he joined the Institute for Hereditary Biology and Racial Hygiene at Goethe University Frankfurt, where he worked for Otmar Freiherr von Verschuer, a German geneticist with a particular interest in researching twins. As Verschuer's assistant, Mengele focused on the genetic factors that result in a cleft lip and palate or a cleft chin. His thesis on the subject earned him a doctorate in medicine (MD) from Goethe University Frankfurt in 1937. In a letter of recommendation, Verschuer praised Mengele's reliability and his ability to verbally present complex material clearly. In 1938, he hired him as a permanent assistant at his institute. As part of his duties, he assessed the racial heritage of applicants for the Aryan certificate, a document required before a person could qualify for government jobs or German citizenship.

On 28 July 1939, Mengele married Irene Schönbein, whom he had met while working as a medical resident in Leipzig. Their only child, a son they named Rolf, was born in 1944.

Military career Mengele joined the Nazi Party in 1937 and the (SS) in 1938. He received basic training in 1938 with the (mountain light infantry) and was called up for service in the (German armed forces) in June 1940, some months after the outbreak of World War II. He soon volunteered for medical service in the , the combat arm of the SS, where he served with the rank of SS- (second lieutenant) in a medical reserve battalion until November 1940. He was next assigned to the SS Race and Settlement Main Office in Poznań, where one of his assignments was evaluating candidates for Germanization.

At the end of 1940, Mengele was assigned to the engineering battalion of the 5th SS Panzer Division Wiking, initially as an assistant medical officer and as the primary medical officer from October 1941. His unit was sent to the Ulm area for training in April 1941 and then to an area southeast of Lublin to await the commencement of Operation Barbarossa, the German invasion of the Soviet Union. The unit crossed into Ukraine on 30 June. On 2 July, the commander of the division's Westland Regiment was killed by a sniper. In response, members of the Wiking Division killed several thousand Jews. This was the beginning of a pogrom by the Wiking Division that continued into Zolochiv and nearby areas until 4 July. German historian Kai Struve estimates the total number of Jewish civilians killed by the Wiking Division in their first week of action during Barbarossa at 4,280 to 6,950 people. Historian David G. Marwell states that while Mengele did not participate in these killings, he must have known what was taking place. Mengele was awarded the Iron Cross 2nd Class on 14 July for bravery. The unit continued to see action in Ukraine and Russia as part of Case Blue (June to November 1942) and was ordered to move towards Stalingrad in late December.

After rescuing two German soldiers from a burning tank, Mengele was decorated with the Iron Cross 1st Class, the Wound Badge in Black, and the Medal for the Care of the German People. In mid-1942, he was seriously wounded in action near Rostov-on-Don and declared unfit for further active service. Following his recovery, he was transferred to the headquarters of the SS Race and Settlement Main Office in Berlin. He was promoted to the rank of (captain) in April 1943. For four months in early 1943, he again worked as an assistant to Verschuer, who was now at the Kaiser Wilhelm Institute of Anthropology, Human Heredity, and Eugenics in Berlin.

Auschwitz

In 1942, Auschwitz II-Birkenau, originally intended to house slave laborers, began to be used instead as a combined labour camp and extermination camp. Prisoners were transported there daily by rail from all over Nazi-controlled Europe. By July 1942, SS doctors were conducting selections where incoming Jews were segregated, and those considered able to work were admitted into the camp while those deemed unfit for labor were immediately murdered in the gas chambers. Those selected to be killed, about three-quarters of the total, included almost all children, women with small children, pregnant women, all the elderly, and all of those who appeared (in a brief and superficial inspection by an SS doctor) to be not completely fit and healthy.

In early 1943, Verschuer encouraged Mengele to apply for a transfer to the concentration camp service. Mengele's application was accepted and he was posted to Auschwitz in May 1943, where he was appointed by SS- Eduard Wirths, chief medical officer at Auschwitz, to the position of chief physician of the Romani family camp at Auschwitz II-Birkenau. The SS doctors did not administer medical treatment to the Auschwitz inmates, but supervised the activities of inmate doctors forced to work in the camp medical service. As part of his duties, Mengele was one of the doctors who made weekly visits to the hospital barracks and ordered any prisoners who had not recovered after two weeks in bed to be sent to the gas chambers.

Mengele's work also involved carrying out "selections": sorting the newly-arrived inmates into two groups: those who would be admitted to the camp, and those who would be killed immediately. He would sometimes visit the selection ramp when not on duty in the hope of locating sets of twins for his experiments. He also looked for physicians, pharmacists, and other medical professionals who could potentially assist him in his research. In contrast to most of the other SS doctors, who viewed selections as one of their most stressful and unpleasant duties, he undertook the task with a flamboyant air, often smiling or whistling. He was one of the SS doctors responsible for supervising the administration of Zyklon B, the cyanide-based pesticide that was used for the mass killings in the Birkenau gas chambers. He served in this capacity at the gas chambers located in crematoria IV and V.

When a typhus epidemic began in the women's camp, Mengele cleared one block of six hundred Jewish women and sent them to be killed in the gas chambers. The building was then cleaned and disinfected, and the occupants of a neighboring block were bathed, deloused, and given new clothing before being moved into the clean block. This process was repeated until all of the barracks were disinfected. Similar killings and disinfections were used for later epidemics of scarlet fever, measles, and other diseases. For these actions, Mengele was awarded the War Merit Cross (Second Class with swords) and was promoted in 1944 to First Physician of the Birkenau subcamp.

Human experimentation and research

Mengele used Auschwitz as an opportunity to continue his anthropological studies and research into heredity, using inmates for medical experimentation. For this purpose, he set up his research facility in the Romani family camp. He was particularly interested in identical twins, people with heterochromia iridum (eyes of two different colors), people with dwarfism, and people with physical abnormalities. He also studied blood proteins, did anthropological studies of the Romani population, and collected specimens for forwarding to the SS Medical Academy in Graz. A grant was provided by the German Research Foundation at the request of Verschuer, who received regular reports and shipments of specimens from Mengele. The grant was used to build a pathology laboratory attached to Crematorium II at Auschwitz II-Birkenau. Miklós Nyiszli, who was forced to work on Mengele's behalf due to his pathologist background, prepared specimens and performed autopsies for this laboratory.