This paper introduces the key themes addressed in the volume Religious and Identity-Based Roots of the War in Ukraine (Routledge, 2026) and establishes the conceptual framework for the panel's broader discussion. It focuses on the transformation of identity models following the outbreak of the war, with particular attention to developments within the Ukrainian Orthodox Church, formerly under the jurisdiction of the Moscow Patriarchate, as well as to the reasons behind the shift in the meaning of autocephaly—once understood as ecclesiastical independence and now also linked to political autonomy. The analysis highlights how this transformation was primarily driven by Metropolitan Onufriy's stance in response to Patriarch Kirill's close alignment with state power rather than with the faithful. This shift has contributed to a more decisive struggle for Ukrainian self-determination and the rejection of Russian interference. The paper examines how the war in Ukraine extends beyond political and economic motives, constituting a struggle for the appropriation of cultural identity and historical heritage. Central to this analysis is the narrative of Kyivan Rus' foundation, which has served as an essential reference point in the strengthening of Russia's projection of power both domestically and internationally. The paper further explores the characteristics and historical development of the Russkyi Mir (Russian World) concept and its relationship to Church-State interaction. Particular attention is devoted to the impact of these dynamics on the path toward Ukrainian autocephaly from the dissolution of the Soviet Union, analyzing Patriarch Kirill's positioning regarding the war and the religious narratives used to legitimize Russian aggression.