Those who died in Auschwitz were brought there due to their religious beliefs political convictions, genetic origins, sexual preference, race or profession. They died for no reason, for no crime and with no justifiable explanation. Some could deny their affiliations; others could not deny their origins. This list is not complete, Auschwitz contained a mishmash of inmates that arrived there for a variety of reasons, but these were the main groups.

1. Jews made up 90% of the 1-3 million who died in Auschwitz between June 1940 and January 1945. The exact figure is hard to calculate as about 70% of prisoners arriving by train were sent directly to the gas chambers and not even registered or given a number. The Jews came from all over Europe. The first arrival of Jews at Auschwitz was 150,000 in February 1942, and they were gassed on arrival. At first Jews wore a yellow star overlapped with an upturned red triangle, this was later given a yellow outline. The red triangle was for political prisoners and Jews were most often termed political.

2. Homosexuals were not part of Hitler's plan, 100,000 German male homosexuals were arrested and 50,000 imprisoned either in regular jails or camps. Initially in the camps they were identified by the number 175 (after paragraph 175 of the German criminal code) on the back of their shirts, and a black dot on the front, this was later replaced by a pink triangle. The pink triangle perhaps came from the "Pink List" that the German Police had compiled of names of homosexuals. The first to arrive at Auschwitz were 48 German Homosexuals. In his trial Rudolph Hess testified that many homosexuals were "reeducated" and released. Some of this reeducation consisted of medical experiments to try and turn homosexuals into heterosexuals; the experiments included castration and hormone injections. 5,000-15,000 male homosexuals were imprisoned in Nazi concentration camps. They were excluded from the Holocaust 60th anniversary of the Liberation of Auschwitz Memorial Day.

3. Intellectuals, the elite, leaders in culture and science, spiritual leaders and ethnic minorities. These were mainly from Poland at first and later from other countries. People with titles, or who were influential were removed from society.

4. Handicapped were sent to Auschwitz as well. As early as 1933 law was passed that anyone with a hereditary disease be sterilized. Patients in mental institutions were the main targets. Euthanasia centers were established and thousands of mental patients were killed and cremated. In all 200,000-250,000 ill and mentally retarded people were exterminated, some were sent to Auschwitz and many underwent experiments in the camp.

5. 728 Polish Political activists arrived on the first mass transport to Auschwitz in June 1940 from Tarnow, a concentration camp for political prisoners, which had been operating since 1936. The Polish were targeted before the Jews in Poland, and being a "political" prisoner was often used as an excuse for incarceration. Political Prisoners wore red triangles in Auschwitz.

6. Gypsies arrived from Germany, Austria and what is today the Czech Republic in February 1943. The section where they were imprisoned came to be known as The Gypsy Family Camp. At least 23,000 were believed to have been deported to this camp and approximately 21,000 died. Gypsies were categorized as asocial along with prostitutes and vagrants. This group of asocials wore black triangles.

7. Soviet prisoners were the first to test out Zykon B gas when the SS killed 600 of them along with 250 ill inmates in September 1941. In all approximately 15, 00 Soviet prisoners of war were exterminated in Auschwitz. The Soviet prisoners wore their original army uniforms with a strip pained on it in oil paint and the letters SU. There were other categories of Soviets who had been "reeducated and they wore an E.

8. Polish people were among the first to be sent to Auschwitz, starting with Polish criminals and Polish political activists. The Polish inmates wore an upside down pink triangle with the letter P on it, instead of the Jewish star badge. Approximately 74,000-140,000 Poles died in Auschwitz.

9. Jehovah Witnesses were among 40 religions banned in Germany and when Hitler came to power they refused to serve in the army nor did they raise their arms in the Heil Hitler salute. They were singled out by Nazis as a rival ideology and for their pacifist beliefs. Jehovah Witnesses wore a purple triangle and the letters IBV (International Association of Bible Researchers) as camp identification. Unlike Jews they could have denied their beliefs but many chose not to. They continued to practice their faith and resist conforming to camp rules while incarcerated. Hoss called them a "fanatical faith", for this dedication to their beliefs even the camp guards admited them. In all between 2,500 and 5,000 Jehovah Witnesses died in the Nazi camps, with at least 387 being at Auschwitz. Catholics and other religions were also persecuted, but mainly their leaders were sent to camps to avoid them becoming opposition leaders.

10. 30 Criminals from Sachsenhausen were the first inmates of Auschwitz. They were deemed anti-social elements of society and came mostly from Germany. The criminals wore green triangles.

11. Ill people were among the first to be gassed as 250 of them were used along with Soviet prisoners to test the gas.

Auschwitz was also a penal camp for Aryan prisoners and regular criminal prisoners sentenced to penal labor. Prisoners came from all over Europe including one Argentinean and one Chinese man.