at the Warsaw University and the leading historian of the Polish Jews. During the ghetto period, he worked on the Archives of the Judenrat and encouraged education in the Ghetto. When the Nazis arrived in Warsaw,
he refused to flee Poland. Two Nazi “historians” (more particularly Professor Hans Serafim of Cracow, a “theoretician” of the Extermination) ordered articles from him on the Polish Jews for their own, personal work. He died of a heart attack in the Ghetto, in November 1942.
