Fred Diament, a retired clothing manufacturer who dedicated himself to teaching others about the Holocaust after surviving five years in Hilter’s death camps, died November 13, age 81.

Born in Kirschen, Germany, Diament was only 15 years old when he was imprisoned at a camp near Berlin before being moved to Auschwitz. There, his father was beaten to death and one of his brothers was hanged for participating in the camp’s underground resistance.

After surviving the notorious death march from Auschwitz to Germany, he moved to Palestine and fought for Israel’s independence with the Haganah, which became the Israeli army, and in the Sinai campaign of 1956.

He later helped organize one of the first kibbutzes for Holocaust survivors and testified in the Nuremberg trials of Nazi war criminals. His testimony helped convict six of Nazi guards at Sachsenhausen and Auschwitz.

Diament helped plan the World Gathering of Holocaust Survivors in the early 1980s, was president of the 1939 Club, and served on a founding committee of the U.S. Holocaust Memorial Museum.

“We have an obligation to speak out against injustices when we see them,” he told the Daily News of Los Angeles.