European societies have experienced extensive secularization. However, the impact of religion in governing people’s political attitudes and behaviors persists, which has been enhanced by several recent developments, including the growing salience of religious and conservative values for the remaining committed religious people, the rise of radical right parties that use Christianity in their anti-immigrant and nationalist rhetoric, and the increasing number of immigrants from outside Europe that contribute to the diversification of religion in European societies. This dissertation investigates the continuing impact of religion on political attitudes and political behaviors in European societies under a secularizing age as embodied in those developments. I will inquire using aspects of political cleavage, political institution, and political articulation related to religion.

Study I examines how national contexts related to religion (secularization and party polarization on morality issues) moderate the impact of same-sex marriage and partnership legislation on public attitudes towards homosexuality. Using eight rounds of European Social Survey (ESS) data, the study shows that, first, in more secular countries and after partnership legislation has passed, there are more divergences in attitudes towards homosexuality between core religious members and the more secular others, with the former showing more negative attitudes. Second, in countries where political parties are more polarized on morality issues, the impact of partnership legislation is more negative in the general population across religiosity and partisanship; however, this effect is not repeated for marriage legislation. The study uncovers distinct effects of different normative institutions in moderating the relationship between legislation and attitudes through the articulation process.

Study II focuses on the mechanism underlying the relationship between Christian religiosity and voting for populist radical right parties in Europe, using ESS Round 8 data. Mediation analysis shows that the factors suggested by previous theories, including tolerance towards immigrants, pro-social values and social capital, hardly explain the underrepresentation of Christians in radical right voters. On the contrary, Christians and radical right voters across Europe have high ideological compatibility in authoritarian and moral conservative values, highlighting ample political space for radical right parties to articulate within for attracting Christian support that has yet to be successfully capitalized. This finding is against Christianity itself being an antidote to the radical right. It suggests that the enduring religious cleavage linked to mainstream right parties may still explain why Christians avoid voting for radical parties.

Study III investigates the role of religion in mobilizing immigrant political participation in the context of Sweden, using the 2010 Level of Living Survey for the Foreign Born and Their Children (LNU-UFB) data. Contrasting the theoretical expectations, this study finds little evidence that religion mobilizes immigrants to participate in politics; actually, religious attendance is found to be negatively related to political participation. The demobilization effect of religion is stronger for women, first-generation migrants. Those who have experienced religion-based societal discrimination, especially Muslims, are less active in political participation. However, second-generation Muslim immigrants are more active in participating in demonstration than the first generation, possibly due to higher perceived discrimination. The results do not support the theory on religious organizations promoting immigrant political participation in Sweden, nor is there suggestive evidence for the emergence of immigrant or Muslim political cleavage in the Swedish context.