This study provides a concise reinterpretation of Frank Ryan's Controversial life (1902-44) and political legacy based on primary sources including much previously unpublished material.

It examines the connections between Ryan's personal life and political outlook against the background of radical politics in inter-war Ireland and Europe. In particular it seeks to explain idealogical motives behind Ryan;s curious political journey from anti-Treaty republicanism to socialist anti-fascism in Spain, and his subsequent collaboration in Nazi Germany.