Using a dataset of higher education institutional alliances within the framework of the European University initiative (EUi), we test empirically whether the policy-defined goal of a relative balance between "excellence and inclusiveness" within the scheme has been achieved. Specifically, we provide a descriptive and analytical account of the diversity of the higher education institutions (HEIs) participating in the EUi, the composition of--as well as the mechanisms behind--the formation of individual alliances. We observe that alliance formation activated the deep sociological mechanisms of hierarchisation, with the alliances largely reproducing the existing "hierarchy of European HEIs." Specifically, we argue that the global-level stratification hierarchy cast by rankings influences the participation of individual institutions and--although to a more limited extent--the formation/structure of the alliances. Further, we demonstrate that the EUi has strengthened existing ties since most alliances thus far have built on existing forms of collaboration. However, we also show empirically that some of the distinctive policy design measures, namely the requirement for broad geographical coverage and generically framed rules for participation, as well as opening the initiative to new alliances and encouraging enlargement of the existing ones, have generated opportunities for involvement of the lower-status institutions. This broadened the scope of the EUi beyond the core of top-ranked research universities located in the knowledge production centres of Europe. We suggest that these observations may have important implications for how the intended extension of the EUi may be implemented in the future.