During adolescence, young people are stimulated to rethink who they are and who they want to become considering their overall strengths and talents. They do so within various different identity domains (e.g., which career to choose), including those related to their belonging to social groups (e.g., gender, nationality). Within the European context, one potentially important social group identity is the European identity. On the one hand, adapting a European identity is assumed to be a crucial factor for securing the continuous stability of the European Union. On the other hand, a European identity could act as a potentially unifying umbrella identity for the ethnically diverse people living in Europe. Past research on European identity rarely examined its development, but focused on cross-sectional associations. Therefore, how European identity develops across different time-scales, what adolescents think being European means, and how this content relates to identity processes as well as other predictors remains mostly unexamined. This dissertation aimed to address these gaps by answering four research questions: (1.) How does European identity develop on the mid- and short-term time scale? (2.) How are daily processes related to mid-term change? (3.) How does media influence daily processes of European identity development? (4.) What does it mean to be European? These four research questions were addressed in three empirical studies.

In the first study, I examined adolescents’ European identity formation on a short- and mid-term time scale, and the time-scales’ interrelations. To assess identity formation, I considered three processes of identity formation: commitment, in-depth exploration and reconsideration of commitment. I conducted latent growth curve analysis and assessed rank-order stability and profile similarity for both time-scales. I ran conditional LGCMs to examine both time-scales’ associations with each other. I found a significant increase of all identity processes from the beginning to the middle of the school year and a significant decrease from the middle to the end of the school year. Across ten days, growth curves varied for the identity processes. Stabilities were high for both time-scales. Commitment at the beginning of the school year was negatively associated with fluctuations in commitment half a year later. Fluctuations of commitment were associated with a decrease in commitment from the middle to the end of the school year.

In the second study, I examined daily media influences on European identity commitment and affects towards the EU, as well as indirect effects via populistic attitudes. Negatively perceived political media content can foster populistic attitudes, which in turn negatively affects European identity commitment and affect towards the EU. I estimated the hypothesized associations using multilevel structural equation models and dynamic structural equation models. Neither populistic attitudes nor negative media content were significantly associated with European identity commitment within days or across days. However, negative media content was associated with higher populistic attitudes and indirectly associated with negative affect towards the EU on the same day.

In the third study, I examined adolescents’ understanding of being European and how it relates to intolerance towards refugees and newly arrived people, EU support, and other predictors including identity processes. It is commonly assumed that European identity is defined in an ethnically inclusive and civic manner. Therefore, it should be associated with positive intergroup attitudes and support for the EU. However, it is an open question whether adolescents conceptualize a European identity ethnically inclusive or civically. European identity content was assessed via open-ended answers and five close-ended questions. The answers were content coded and together with the close-ended questions included in latent class analysis. Three European identity classes emerged: a living-based (47%), a culture & value-based (27%) and an ancestry-based class (26%). Classes did not differ with regard to EU support, but to intolerance (highest: ancestry-based, lowest: culture & value-based). Class membership was significantly associated with commitment and in-depth exploration, i.e., participants in an ancestry-based class showed highest levels of commitment and participants in the ancestry- or living-based class showed higher levels of in-depth exploration than those in the culture & value-based class.

My results highlight the importance of examining different time-scales and different identity domains to capture European identity development comprehensively. They further indicated that short-term fluctuations are associated with long-term development. These short-term fluctuations seem to be unaffected by negative media content, at least across ten days. Finally, my results indicated that adolescents differed in their understanding of being European and that it is important to consider how youth define Europeanness to understand European identity’s effect on adolescents’ views.