Understanding populist beliefs through relative deprivation: Correlational and experimental evidence for a group-based approach

Despite the fact that the landscape of today’s democratic countries has been significantly shaped by populism, much remains to be known about the psychological processes that explain its appeal. To understand why support for populism varies among people who experience similar socioeconomic conditions, this thesis explores how subjective experiences of injustice, self-uncertainty, and social identity interact to shape the key components of populist attitudes: anti-elitism and demands for popular sovereignty. Drawing from the ideational approach to populism and informed by Social Identity Theory and Uncertainty Identity Theory, this thesis proposes a framework grounded in three mechanisms: relative deprivation, self-uncertainty, and identification with the people. I address these questions through a set of five studies completed in Switzerland, the United Kingdom, and eight countries in Europe. I present them in two empirical chapters that combine correlational and experimental designs. Chapter 4 (Studies 1 to 3) shows that perceived disadvantage mediates the relationship between socioeconomic status and anti-elitism, and that experimental manipulation of group-based injustice increases populist attitudes. Chapter 5 (Studies 4 and 5) provides evidence that both self-uncertainty and people identification predict populist attitudes, that people identification mediates the relationship between relative deprivation and populist beliefs, and that self-uncertainty moderates parts of this relationship only weakly. Overall, the results suggest that populist support arises not only from material or structural conditions but from the ways in which individuals interpret subjective disadvantage through their identity and uncertainty. In the present thesis, I incorporate these processes into one model and contribute to political psychology by clarifying how socio-political grievances are internalised, and translated into populist belief systems.