Otto Adolf Eichmann ( EYEKH-mən, German: [ˈɔtoː ˈʔaːdɔlf ˈʔaɪçman]; 19 March 1906 – 1 June 1962) was a German-Austrian SS-Obersturmbannführer and one of the major organisers of the Holocaust – the so-called "Final Solution to the Jewish Question" in Nazi terminology. He was tasked by SS-Obergruppenführer Reinhard Heydrich with facilitating and managing the logistics involved in the mass deportation of millions of Jews to ghettos and extermination camps in Nazi-occupied Eastern Europe during World War II. Eichmann was captured by Mossad agents in Argentina on 11 May 1960 and subsequently found guilty of war crimes in a widely publicised trial in Jerusalem, following which he was executed by hanging in 1962.

After doing poorly in school, Eichmann briefly worked for his father's mining company in Austria, where the family had moved in 1914. He worked as a travelling oil salesman beginning in 1927, and joined both the Nazi Party and the SS in 1932. He returned to Germany in 1933, where he joined the Sicherheitsdienst (SD, "Security Service"); there he was appointed head of the department responsible for Jewish affairs – especially emigration, which the Nazis encouraged through violence and economic pressure. After the outbreak of the Second World War in September 1939, Eichmann and his staff arranged for Jews to be concentrated in ghettos in major cities with the expectation that they would be transported either farther east or overseas. He also drew up plans for a Jewish reservation, first at Nisko in southeast Poland and later in Madagascar, but neither of these plans was carried out.

The Nazis began the invasion of the Soviet Union in June 1941, and their Jewish policy changed from emigration to extermination. To coordinate planning for the genocide, Reinhard Heydrich, who was Eichmann's superior, hosted the regime's administrative leaders at the Wannsee Conference on 20 January 1942. Eichmann collected information for him, attended the conference, and prepared the minutes. Eichmann and his staff became responsible for Jewish deportations to extermination camps, where the victims were gassed. Germany invaded Hungary in March 1944, and Eichmann oversaw the deportation of much of the Jewish population. Most of the victims were sent to Auschwitz concentration camp, where about 75 per cent were murdered upon arrival. By the time the transports were stopped in July 1944, 437,000 of Hungary's 725,000 Jews had been killed. Dieter Wisliceny testified at Nuremberg that Eichmann told him he would "leap laughing into the grave because the feeling that he had five million people on his conscience would be for him a source of extraordinary satisfaction."After Germany's defeat in 1945, Eichmann was captured by US forces, but escaped from a detention camp and moved around Germany to avoid re-capture. He ended up in a small village in Lower Saxony, where he lived until 1950, when he moved to Argentina using false papers he obtained with help from an organisation directed by Catholic bishop Alois Hudal. Information collected by the Mossad, Israel's intelligence agency, confirmed his location in 1960. A team of Mossad and Shin Bet agents captured Eichmann and brought him to Israel to stand trial on 15 criminal charges, including war crimes, crimes against humanity, and crimes against the Jewish people. During the trial, he did not deny the Holocaust or his role in organising it, but said he was simply following orders in a totalitarian Führerprinzip system. He was found guilty on all of the charges, and was executed by hanging on 1 June 1962. The trial was widely followed in the media and was later the subject of several books, including Hannah Arendt's Eichmann in Jerusalem, in which Arendt coined the phrase "the banality of evil" to describe Eichmann.