“Council democracy” is a particular form of democratic socialism that strives towards democratic self-governance on the basis of active, free, and associated individuals working cooperatively within a federated council system. Both in political practice and in social theory, “council democracy” has resurfaced periodically in the past, most notably in the interwar period, in the “long 1960s,” and since the turn of the 21st century. This book offers a novel theoretical and methodological approach to the study of “council democracy.” It focuses on the processes that led to the emergence of two of the foundational and most radical instances of “council democratic” movements in Germany during the German Revolution (1918-1919) and in Italy during the biennio rosso (1919-1920). With all their diversities, ambiguities, and shortcomings, these movements, in varying degrees, sought democratic alternatives to autocratic relations, from local to state levels, and to economic relations, from workplace to national levels. The book shows how the processes through which state-led war mobilization transformed the contours of class struggle laid the ground for the emergence of “council democratic” movements with specific characteristics in Germany and Italy and not in the United Kingdom and France.