During the war, Walter Kulka and his wife Luisa lived at Bamberger Straße 51 in Berlin-Schöneberg. Kulka ran a removals company founded by his father Willy. In 1939 the Jewish sisters Ilse and Margarete Berghausen hired Walter Kulka to transport their belongings to South America. However, they could no longer emigrate after the war began, and their furniture was put in storage. Ilse Grün, as she was called after her marriage, had to go into hiding with her husband Gerhard in January 1943. During the Grüns’ time underground, the Kulkas supported them with food ration coupons. Ilse Grün survived and in 1947 emigrated to the United States, where she married the Jewish businessman Ludwig Löwenberg.
Later, Ilse Grün stated that Kulka’s parents, who lived in the same building, had also provided food to support her and her sisters Margarete Berghausen and Lieselotte Salomon, also in hiding, and Lieselotte’s husband, the rabbi Hermann Salomon. All three were caught and murdered in Auschwitz, however.
In 1982 Walter and Luise Kulka and others of Ilse Grün’s helpers were honored by the Israeli Holocaust memorial center Yad Vashem as Righteous Among the Nations.