The EU’s structuring role for interorganisational relations: the case of AU-ECOWAS on peacekeeping in West Africa

African regional organisations have been intervening in state crises for decades. Although the AU and subregional organizations are expected to function based on subsidiarity, no clear official division of labour exists among them. In practice, they have found differing roles in conflict management in Africa. However, the factors that drive their learning processes and adaptations under particular circumstances remain unclear. Based on the fact that peacekeeping operations in Africa are significantly supported by external actors, particularly, their financial assistance, this study analyses how European Union (EU) financial assistance has impacted the African Union (AU)-Economic Community of West African States (ECOWAS) relationship. An empirical analysis of the EU’s financial assistance for conflict management in West African countries demonstrates that EU support has helped develop the division of labour between the AU and ECOWAS over the years, especially since the period from the late 2000s. The research presented here contributes to studies on interorganisational relations by showing a case of the EU’s structural influence on the AU-ECOWAS relationship in their intervention to key recent crises in West Africa.