In the nineteenth and early twentieth century, Swedish gymnastics won a large following across the world. Employing the concepts of educationalisation and gender, I will explore how the physical education of girls was conceptualised and justified in the Swedish system during the latter half of the nineteenth century. Focusing on the publications of Anton Santesson (1825–1892), who was one of the main authors on girls’ gymnastics in Sweden, I will show how girls’ gymnastics was conceptualised as a response to a social, cultural and physical crisis, which was perceived as partly stemming from the detrimental effects of education on girls’ bodies and minds. Girls’ gymnastics was thus construed as vital to the future of the Swedish nation. While men and manliness remained fundamental to the strength of the nation, girls’ gymnastics was vital to women’s rearing of boys and thus instrumental to the development of masculinity in men.