The only known photographs of the deportation of the Jewish population in the German city of Hamburg have been discovered in a German police officer’s secret photo album. Until now, no visual record of the deportations from Hamburg was known to exist. But researchers have now identified three photographs taken in October 1941. For 84 years, these images remained hidden in the private album of a German policeman who served in Unit 101 of the Ordnungspolizei, or “green police,” a unit involved in deporting and murdering tens of thousands of Jews during the Holocaust. However, the policeman’s personal file indicates...