The article analyzes the evolution of the Armenian-Azerbaijani conflict from a broad comparative-historical perspective, focusing on the Nagorno-Karabakh issue and the role of the European Union (EU) in its resolution. The study compares the internal dynamics of the negotiation process between the parties to the conflict and external factors related to the EU’s peacekeeping initiatives. The author argues that despite the dominant role of the Karabakh conflict in relations between Baku and Yerevan, it was not the only source of contradictions. The confrontational paradigm of interaction has deep historical roots that have a serious impact on both state-building and the development of identity, constructed within the framework of mutual antagonism, and in the skeptical attitude towards external mediators. This narrows the possibilities for finding a peaceful solution and compromise, over which the logic of force still prevails. The analysis shows that before 2020, the EU's opportunities to participate in the settlement were limited under the previous status quo and the established negotiation format, although the instruments of European peacekeeping gradually developed. In turn, the transformation of the previous balance after the Second Karabakh War (2020) created conditions for the activation of the EU's role as a multilateral actor. During the transition period of 2020-2023, Brussels played a significant role in shaping the new architecture of the negotiations, contributing to the development of a peace agreement between Armenia and Azerbaijan. Yet at the subsequent stage, the parties abandoned mediation in favor of direct bilateral negotiations, which indicates utilitarian perception of EU mediation. New US peacekeeping initiatives in 2025 moved the EU to the periphery of the peace process. It is concluded that Brussels cannot have a significant and sustainable impact on the normalization of Armenian-Azerbaijani relations due to the situational approach of the parties to external assistance in the negotiations.