Steinberg passed away Friday morning in Manhattan from complications of lymphatic cancer, his wife Sharon told The New York Times.
Steinberg, who led the congress from 1978 to 2004 before becoming vice president of the American Gathering of Jewish Holocaust Survivors and their Descendants, was known as a fierce defender of Jewish interests worldwide. Holocaust survivor and author Elie Wiesel issued a statement to be read at Steinberg's funeral:
"Whenever Jews were in danger, or Jewish honor offended, he vigorously yet elegantly spoke up. Whenever Jewish memory was attacked, he attacked the attacker."
During Steinberg's time with the World Jewish Congress, he won billions of dollars in restitution for holocaust survivors and descendants.
He spearheaded the effort to expose Austrian presidential candidate Kurt Waldheim as a former Nazi during the 1986 presidential race. Although Waldheim, who tried to hide his past, went on to win the election, Steinberg dismissed him saying, "In the whole world it will be said that a former Nazi and a liar is the representative of Austria."