The article shows historical memory as one of the key issues in the interdisciplinary field of social research since it determines socio-cultural and political aspects of the life of social groups. It forms the traditions and defines values necessary for the society development, accomplishes integrative function for the nation, ethnic group, accumulates experience of generations and enriches historical consciousness. However, the other side of historical memory as a significant factor of ethnic and religious conflicts is also highlighted. Firstly, historical memory has a conflict potential connected with identity of the social community (ethnic, religious, national) since self-perception of “we” always includes opposition to others, strangers, usually hostile communities. Secondly, historical memory could also mobilize for struggle. The traumatic aspects of collective memory are successfully used in ethno-confessional conflicts for political manipulation and tension escalation It is a time-consuming task to build new relationships, to shift hostility to a neutral phase and then to the stage of cooperation, equality and integration. Contradictory nature of historical memory requires a systematic approach to peace-making policy, to changes in views, to repressing aspects of ethnic and religious conflicts from historical memory. The article presents the results of sociological research aimed at studying different aspects of the historical memory of the Russian society and several post-Soviet countries. The study highlights the dual role of historical memory — ethno integration and division. The authors analyze the personified memory of ethno-confessional conflicts and its reflection in modernity resulting in the information wars, propaganda of enmity and mythologems about the heroes and victims of the lost past.