Navigating widening and deepening: the European Council, geopolitical motives, and Union enlargement

Following Russia’s full-scale invasion of Ukraine in February 2022, the European Council has again moved enlargement high on the agenda of the European Union (EU). From an academic perspective, this raises several interesting issues: first, about the motivations to start enlargement negotiations; second, about the realization of enlargement and the link between Union widening and deepening; and third, about similarities and differences compared to previous enlargement rounds. This article analyzes why and how the European Council, the actor de facto in charge of opening and concluding accession negotiations, addressed the enlargement topic over time. Evaluating all summit conclusions since 1961 and other relevant documents, it finds that geopolitical motives about security, stability and influence featured prominently in European Council deliberations. At the same time, European Council members regularly linked their guidelines for widening with concerns about the EU’s internal functioning.