Mauthausen-Gusen concentration camp in the context of "Linz"

Nazi human experimentation was a series of medical experiments on prisoners by Nazi Germany in its concentration camps mainly between 1942 and 1945. There were 15,754 documented victims, of various nationalities and ages, although the true number is believed to be more. About a quarter of documented victims were killed and survivors generally experienced severe permanent injuries.

At Auschwitz and other camps, under the direction of Eduard Wirths, selected inmates were subjected to various experiments that were designed to help German military personnel in combat situations, develop new weapons, aid in the recovery of military personnel who had been injured, and to advance Nazi racial ideology and eugenics, including the twin experiments of Josef Mengele. Aribert Heim conducted similar medical experiments at Mauthausen.

Extermination through labour (or "extermination through work", German: Vernichtung durch Arbeit) is a term that was adopted to describe forced labor in Nazi concentration camps whose inmates were held in inhumane conditions and suffered a high mortality rate; in some camps most prisoners died within a few months of incarceration. In the 21st century, research has questioned whether there was a general policy of extermination through labor in the Nazi concentration camp system because of widely varying conditions between camps. German historian Jens-Christian Wagner argues that the camp system involved the exploitation of forced labor of some prisoners and the systematic murder of others, especially Jews, with only limited overlap between these two groups.

Some writers, notably Aleksandr Solzhenitsyn, have written that the Soviet Gulag system was also a form of extermination through labour. Similar statements have been made about the Laogai system under Mao Zedong's China.

Aribert Ferdinand Heim (28 June 1914 – 10 August 1992), also known as Dr. Death and Butcher of Mauthausen, was an Austrian Schutzstaffel (SS) doctor. During World War II, he served at the Mauthausen-Gusen concentration camp in Mauthausen, killing and torturing inmates using various methods, such as the direct injection of toxic compounds into the hearts of his victims.

After the war, Heim lived in Cairo, Egypt, under the alias of Tarek Farid Hussein after his conversion to Islam. In February 2009, after years of attempts to locate him, German television network ZDF had found Heim's passport and other documents in Cairo. It was then reported that Heim had died there on 10 August 1992 from complications of rectal cancer, according to testimony by his son Ruediger and lawyer. This information, though set forth by a German court, was questioned by Efraim Zuroff, a leading Nazi hunter of the Simon Wiesenthal Center. Zuroff stated that on a visit to Puerto Montt, Chile, in July 2008, Heim's daughter told him that Heim had died in 1993 in Argentina. In 2012, a court in Baden-Baden confirmed again that Heim had died in 1992 in Egypt, based on new evidence provided by his family and lawyer. The Wiesenthal Center continued to dispute these findings, and Heim remained on the list of most-wanted Nazi war criminals until 2013.