This presentation explores the dynamic and contested nature of cosmopolitan memories, highlighting their varied paths over the past two decades. It explores how these memories shape both national and transnational identities, foster potential solidarities, and grapple with historical legacies in today's rapidly changing global landscape. The original concept of Cosmopolitan Memory emerged in the late 1990s, a period marked by the rise of international jurisdiction, humanitarian interventions, and the establishment of a human rights regime. Over the following decade, we witnessed how cosmopolitan memories could transform both domestic and international relations. Emphasizing intercultural dialogue, reconciliation, and solidarity among diverse communities, this phenomenon was particularly prominent in Europe, where the cosmopolitanization of Holocaust memory served as a unifying force. However, this era of unity was short-lived, as it became clear that while Holocaust memory served as an official source of shared values, it also exacerbated divides within Europe, especially between the West and East, and fueled neo-nationalist sentiments, further exacerbating mnemonic tensions.