In stark contrast to the Nigerian Civil War, when the Ivorian President Félix Houphouët-Boigny supported the secessionist Biafran Republic against the Federal Military Government, early postcolonial relations between Côte d’Ivoire and Nigeria were close. This ‘entente cordiale’ was underpinned by the friendship of Houphouët-Boigny and the Nigerian Prime Minister Sir Abubakar Tafawa Balewa, who were both anti-communist, pro-western, capitalist, and in favour of African co-operation instead of integration. Yet it was Ghana’s Kwame Nkrumah who, through his criticism and alleged subversive machinations against Côte d’Ivoire and Nigeria, gave the two countries their common purpose. Focusing, unlike previous scholarship, on the military and strategic responses of Abidjan and Lagos to Accra, and based on multi-archival research, this article argues that the Nkrumah factor brought about a strategic alignment between Côte d’Ivoire and Nigeria. It also shows, however, that despite a common threat assessment, domestic politics had a decisive and diverging impact on the foreign and security policies of the two states, and that regional and colonial legacies turned out to have a more significant impact on early postcolonial Africa than did the Cold War. The article sheds light on African agency, while simultaneously going beyond and, more significantly, offering an alternative perspective to the Cold War-driven historiography of early postcolonial Africa, and its tendency to focus on external rather than African actors.