The World Congress of Mothers in Lausanne in 1955 brought together over 1000 women from more than sixty countries. The Congress was held under the auspices of the Women’s International Democratic Federation (WIDF). In this article, the relationship between the World Congress of Mothers and the Japan Mothers’ Congress (Nihon Hahaoya Taikai), which has met annually since 1955, is considered. This provides a suitable locus for exploring the dynamic interrelationships of local, national, international and global politics, especially from 1953, when women from Japan started to interact with the WIDF, until the late 1950s, by which time the Hahaoya Taikai meetings were well established there. Three stages are explored—preparations for the World Congress of Mothers in Lausanne by the WIDF and by delegates from Japan; the participation of the Japanese delegates in the World Congress in 1955, and the legacy of the Japanese delegates’ participation in the Lausanne Congress. By focusing on these three stages in one country’s interactions with an international organisation, we can gain a more complex understanding of the dynamics of transnational politics and the embeddedness of global politics in local contexts. Although common issues were often discussed in different places, discussions in each place were inflected by their local contexts. The positioning of a particular nation in the global geopolitics of the Cold War also affected the possibilities of participation by individuals in such international congresses.