Wiesenthal, a Holocaust survivor who was imprisoned in five concentration camps, dedicated his life to memorializing the 6 million Jews who were murdered during World War II. After he was freed in 1945, he gave a list of names of Nazi officials to the U.S. government and helped gather evidence for the first trials against war criminals. From then on, Wiesenthal continued to search for Nazis that he could prosecute. Wiesenthal wasn't interested in vengeance, instead, he said that he wanted to make sure that Nazi crimes were "brought to light so the new generation knows about them, so it should not happen again," per The New York Times. His work made him the most famous Nazi hunter in history.