This book critically examines debates and projects advocating federal, confederal, and cooperative solutions in the Balkans and East-Central Europe from the 19th century to the present. It counters the “powder keg” narrative by showcasing historical integration plans, from Austria-Hungary’s reforms to Yugoslavism and EU initiatives. Contributions analyze intellectual and political efforts to mitigate nationalism, emphasizing the region’s potential for peaceful coexistence. The volume bridges gaps in historical knowledge, appealing to scholars and general readers interested in alternative transnational developments. Its content is the result of a senior-junior teamwork from MIREES, a Joint MA program of the Universities of Bologna, V.M. Kaunas, and Zagreb.