This paper addresses the role of collective memory of post-Holocaust crimes in contemporary Polish−Jewish relations. We examined how reminding Polish participants of ingroup atrocities affects constructive as well as destructive attitudes and behavioral intentions toward the Jewish victim group. We address the question of how experimentally induced feelings of cultural closeness between the outgroup and the ingroup modify the effects of these reminders on intergroup relations. Our two experiments suggest that perceived sharing of culture is a crucial factor in dealing constructively with the “problematic past” in intergroup relations. In the baseline condition (where cultural closeness of Jews and Poles was not made salient), reminders of ingroup atrocities activated group-defensive strategies, resulting in more negative intergroup attitudes and dehumanization of Jews. In stark contrast, in the “culturally close” condition (where feelings of shared culture were induced), reminders of ingroup atrocities actually resulted in more positive intergroup attitudes and humanization of Jews.