Chapter 2 discusses the normative-theoretical conditions for and the necessity of EU democratisation. On this basis, the contested concept of “European identity” is theorised, conceptualised, and operationalised. The relevant theories and approaches of EU democratisation and European identity are discussed and integrated, the research question is sharpened, and the heuristics of the empirical study is developed in the following steps: Foundational normative theory considerations: the role of democratic identity in the democratisation of the EU is discussed and summarised (Section 2.1); Comparison and integration of theories: a logical comparison of theories is undertaken for the relevant approaches and insights from four areas: (1) democratic theory and (2) construction of collective identities, (3) micro-oriented or quantitative-empirical approaches, and (4) macro-oriented, mostly more qualitative approaches to the study of European identity. Based on this comparison, the normative-theoretical, macro- and micro-oriented approaches are integrated (Section 2.2) and the research question is fixed (Section 2.3)