This editorial introduces a special issue focused on the interdisciplinary study of social identity across time, with particular attention to religious identities and their development in both historical and contemporary contexts. It highlights the need for greater dialogue between disciplines, as identity is examined through diverse theoretical and methodological approaches, including social identity theory, cognitive perspectives, and historical analysis. The issue aims to bridge gaps between research traditions and develop a shared framework for understanding how identities are constructed, maintained, and transformed.

A central theme of the issue is the complex and dynamic nature of social identity as an individual and relational process. Drawing on social identity theory, the editorial emphasizes that identity is not simply a collective phenomenon but also shaped by individual perceptions, motivations, and negotiations. Complementary approaches, such as dialogical self theory, are presented as valuable for understanding how individuals reconcile multiple and sometimes conflicting identities. The contributions in the issue illustrate how identity formation varies even among individuals within the same social group, influenced by different motives such as the need for continuity, distinctiveness, and psychological coherence.

Another key focus is the role of intergroup relations in shaping identity, particularly through processes of differentiation and negative stereotyping. The articles demonstrate how emerging identities often rely on contrasting themselves with outgroups, sometimes through historically constructed narratives that persist over time. Examples include the development of polemical representations in religious traditions and the continued influence of such narratives in modern forms of prejudice, such as antisemitism. These dynamics underline the importance of historical context and the interplay between past and present in identity construction.