This book investigates the evolving political nature of the European Union in the wake of its eastward expansion, questioning whether the organization is evolving into a traditional state or a more fluid imperial structure. Jan Zielonka, a professor of European politics, utilizes extensive empirical data regarding the accession of new member states to challenge conventional integration theories. He argues that the EU is increasingly functioning as a neo-medieval empire characterized by flexible borders and overlapping authorities rather than a centralized federal state.

Experts in European studies recognize this work as a significant contribution to the debate on the EU's long-term institutional trajectory. Readers frequently note the academic density of the prose, which is best suited for students and scholars of international relations and political theory.