The end of the First World War marked a break in gender relations. Women’s enfranchisement in many countries and interwar internationalism offered women new opportunities to participate in international affairs. Activists of the women’s movement used the channels of the League of Nations to advance reforms in the area of women’s rights, humanitarianism and social welfare. Together with child welfare activists, they emphasised the significance of future generations for a peaceful world order. Encouraging the dissemination of a new concept of childhood, they pushed for the recognition of children as individuals with special needs and rights. At the same time, these activities entrenched a gendered idea of global governance based on a sexual division of responsibilities in international affairs which confirmed collective security as a male domain and limited female influence to social and humanitarian affairs. The end of the First World War marked a fundamental break in international relations. After more than 4 years of horrendous killing and economic distress, the Paris Peace Agreement of 1919 raised new hopes with a war-weary public.