This book explores the preoccupation with boyhood in Ontario during the immediate post-war period, 1945-1960. It argues that a traditional version of boyhood was being rejuvenated in response to a population fraught with uncertainty, and suffering from insecurity, instability, and gender anxiety brought on by depression-era and wartime disruptions in marital, familial, and labour relations, as well as mass migration, rapid post-war economic changes, the emergence of the Cold War, and the looming threat of atomic annihilation. In this socio-political and cultural context, concerned adults began to cast the fate of the post-war world onto children, in particular boys. In the decade and a half immediately following World War II, the version of boyhood that became the ideal was one that stressed selflessness, togetherness, honesty, fearlessness, frank determination, and emotional toughness. It was thought that investing boys with this version of masculinity was essential if they were to grow into the kind of citizens capable of governing, protecting, and defending the nation, and, of course, maintaining and regulating the social order. Drawing on a wide variety of sources, Ontario Boys demonstrates that, although girls were expected and encouraged to internalise a special kind of citizenship, as caregivers and educators of children and nurturers of men, the gendered content and language employed indicated that active public citizenship and democracy was intended for boys. An appropriate boyhood in the post-war period became, if nothing else, a metaphor for the survival of the nation.