[4] Greif was the scientific advisor and historical consultant for the exhibition "With Me Here Are Six Million Accusers" which marked the 50th anniversary of Adolf Eichmann's trial in 1961, inaugurated April 11, 2011, at Yad Vashem, Jerusalem.

[5] The exhibition described Eichmann's career at the SS, his personal responsibility for the deportation of millions of Jews to the ghettos and extermination camps, his attempts to hide after the war and the operation of his discovery and seizure in Argentina in 1960.

Greif's book We Wept Without Tears inspired Hungarian director László Nemes to create the film Son of Saul dedicated to the Sonderkommando.

[10][11] Greif spent four years examining archives in research of the genocide in fascist Independent State of Croatia, in which he affirmed a number of more than 700,000-800,000 Serb victims in Jasenovac.

[12][13][14] Dr. Robert Rosett, Senior Historian at the International Institute for Holocaust Research at Yad Vashem, stated that the number of victims murdered at Jasenovac were "many times less than the grossly inflated count of more than 800,000 that was widely touted in the Communist era and has been endorsed by Gideon Greif".

[26] However, following diplomatic fallout in Germany due to his contention that the Srebrenica massacre perpetrated by Bosnian Serb forces in 1995 did not constitute genocide,[23] the German Foreign Ministry in December 2021 announced that the award has been "withdrawn", explaining that the conclusions of the commission headed by Greif "contradict the case law of the International Criminal Tribunal for the former Yugoslavia, the International Court of Justice and the Convention on the Prevention and Punishment of Genocide".

[29] For his involvement "in defense of the truth about the suffering of the Jewish, Serbian and other peoples during the World War II" he was awarded the Golden Medal for Merits of the Republic of Serbia.