The Nazi concentration camp Auschwitz I in Poland, circa 1945. Writing over the gate reads "Arbeit macht frei" (Work Sets You Free). Johann Breyer has admitted to working as a guard at the camp but says he only supervised work parties outside the gates. Uncredited/AP hide caption

itoggle caption Uncredited/AP

The names of Jeffrey Katz's family members are depicted on "stumbling stones" in Lembeck, Germany. His relatives owned a home on the property near the stones, before they were evicted in 1942. Jeffrey Katz/NPR hide caption

itoggle caption Jeffrey Katz/NPR