2.1. Toward growing importance of culture in Western politics

Socio-political transformations of the 1960s in the West, among other consequences, also brought about the so-called “cultural turn” in Western politics. Class-based redistributive conflicts that previously used to dominate political agendas of Western democracies became increasingly overshadowed by conflicts over cultural issues such as minority rights, environment, gender equality, and cultural diversity (Inglehart, Reference Inglehart1977; Inglehart and Welzel, Reference Inglehart and Welzel2005; Kriesi et al., Reference Kriesi, Grande, Lachat, Bornschier and Frey2006; Bornschier, Reference Bornschier2010; Kriesi, Reference Kriesi2010; Ford and Jennings, Reference Ford and Jennings2020). Ample research on the cultural turn then demonstrated that social class and associated socio-economic preferences were losing their previously undoubted explanatory power over voting choice in Western Europe, while non-economic motives for voting choice, on the contrary, became increasingly relevant (Achterberg, Reference Achterberg2006; Bornschier, Reference Bornschier2010; Kriesi, Reference Kriesi2010; Ford and Jennings, Reference Ford and Jennings2020; Pless et al., Reference Pless, Tromp and Houtman2020). Although different studies suggest different explanations as to why the cultural turn in Western politics occurred (i.e., due to economic development and increasing educational attainment (Inglehart, Reference Inglehart1977), or due to globalization and opening of national borders (Kriesi et al., Reference Kriesi, Grande, Lachat, Bornschier and Frey2006; Kriesi, Reference Kriesi2010)), the “triumph of culture” in West European politics has become largely accepted in the social sciences and even led many social scientists to expect further increases in the electoral relevance of cultural issues.

The new cultural dimension of West European politics is generally described as an opposition between cultural progressives, who embrace progressive societal transformations, and cultural conservatives, and who understand these transformations as a threat to traditional identities and national security (Hooghe et al., Reference Hooghe, Marks and Wilson2002; Flanagan and Lee, Reference Flanagan and Lee2003; Bornschier, Reference Bornschier2010; Ford and Jennings, Reference Ford and Jennings2020). To conceptualize this cultural dividing line, most studies lump together attitudes toward such different matters as homosexuality, gender roles, and abortion, alongside attitudes vis-à-vis authority, immigration and cultural diversity, environment and climate change, globalization, and (European) integration (De Witte and Billiet, Reference De Witte, Billiet, De Witte and Scheepers1999; Hooghe et al., Reference Hooghe, Marks and Wilson2002; Flanagan and Lee, Reference Flanagan and Lee2003; Inglehart and Welzel, Reference Inglehart and Welzel2005; Stubager, Reference Stubager2008; Bornschier, Reference Bornschier2010). Flanagan and Lee (Reference Flanagan and Lee2003), for instance, use individual attitudes toward marital faithfulness alongside attitudes toward maintaining social order and respecting authorities to describe the authoritarian–libertarian cultural conflict. Inglehart's description of the “survival versus self-expression” cultural dichotomy similarly refers to attitudes toward gender equality (e.g., men having priority over women on the job market), national pride, and tolerance toward foreigners (Inglehart and Welzel, Reference Inglehart and Welzel2005). The famous GAL/TAN scale (Hooghe et al., Reference Hooghe, Marks and Wilson2002), in its turn, combines traditional morality (e.g., attitudes toward euthanasia and abortion) and attitudes toward authorities.

Besides being a part of a broader cultural dimension, the first group of aforementioned cultural attitudes (i.e., toward homosexuality, gender roles, and abortion) is often singled out as the moral traditionalism–progressiveness value dimension as it refers to matters of life/death, sexuality, procreation, and family and gender roles (Raymond, Reference Raymond2011; Langsæther, Reference Langsæther2019; Pless et al., Reference Pless, Tromp and Houtman2023). Because moral traditionalism in particular is not the primary focus in the cultural turn research, empirical studies in this group rather analyze the electoral relevance of all cultural issues amassed together and expect moral traditionalism to increase in electoral relevance as a part of a broader range of cultural issues (Inglehart, Reference Inglehart1977; Dalton, Reference Dalton and LeDuc1996; Kriesi et al., Reference Kriesi, Grande, Lachat, Bornschier and Frey2006; Kriesi, Reference Kriesi2010). If this rather universalist proposition of the “cultural turn” studies is correct, then:

Looking inside the cultural dimension, Kriesi et al. (Reference Kriesi, Grande, Lachat, Dolezal, Bornschier and Frey2008), however, suggest that moral traditionalism in particular might be an outlier among other cultural issues and might actually lose its political relevance as cultural political agendas move from being centered around religious concerns to revolving around secular issues related to authoritarianism. This hypothesis of a different fate of moral traditionalism has not yet been tested empirically as most “cultural turn” studies still tend to use moral traditionalism and authoritarianism interchangeably to tap into the cultural dimension (see, for instance, how Häusermann and Kriesi (Reference Häusermann, Kriesi, Beramendi, Häusermann, Kitschelt and Kriesi2015) measure “cultural liberalism” via attitudes toward gender roles and homosexuality together with attitudes toward obedience and criminal punishment). Luckily, another strain of social research, namely religious cleavage research, focuses on moral traditionalism–progressiveness in particular and explicitly theorizes about the conditions under which moral traditionalism is likely to lose its electoral relevance (De Koster and Van der Waal, Reference De Koster and Van der Waal2007; Raymond, Reference Raymond2011; Langsæther, Reference Langsæther2019).

2.2. Moral traditionalism–progressiveness and the religious cleavage

The moral traditionalism–progressiveness value dimension in Western Europe typically taps into the opposition between religious, namely traditionally Christian, and secular individuals (De Koster and Van der Waal, Reference De Koster and Van der Waal2007; Raymond, Reference Raymond2011; Langsæther, Reference Langsæther2019; Pless et al., Reference Pless, Tromp and Houtman2023). Religious people are more likely to oppose abortion, as well as condone same-sex marriage and homosexuality because such practices are condemned by traditional Christianity. Secular individuals, on the contrary, hold more progressive views on these matters since their worldviews are not directly influenced by religion and its stances on such matters as abortion, euthanasia, and homosexuality (see, for instance, Finke and Adamczyk, Reference Finke and Adamczyk2008; Nicolet and Tresch, Reference Nicolet and Tresch2009; Halman and Van Ingen, Reference Halman and Van Ingen2015; Storm, Reference Storm2016).

In the electoral realm, it is first of all religious (i.e., Christian and denominational) and broadly conservative parties that cater to religious individuals with morally traditionalist views (Knutsen, Reference Knutsen2004; De Koster and Van der Waal, Reference De Koster and Van der Waal2007; Raymond, Reference Raymond2011; Langsæther, Reference Langsæther2019). Secular progressive voters, on the other hand, typically favor non-religious and non-conservative parties with morally progressive agendas (Kotler-Berkowitz, Reference Kotler-Berkowitz2001; Knutsen, Reference Knutsen2004; De Koster and Van der Waal, Reference De Koster and Van der Waal2007; Dolezal, Reference Dolezal2010; Engeli et al., Reference Engeli, Green-Pedersen and Larsen2012; Euchner and Preidel, Reference Euchner and Preidel2018). These electoral differences comprise the religious cleavage, with attitudes toward moral issues motivating religious voters to favor religious and conservative parties, and secular voters supporting secular, progressive ones (Bartolini and Mair, Reference Bartolini and Mair1990; Raymond, Reference Raymond2011; Engeli et al., Reference Engeli, Green-Pedersen and Larsen2012; Langsæther, Reference Langsæther2019). Unlike the studies on the cultural turn in politics, research on the religious cleavage focuses specifically on the moral traditionalism–progressiveness value dimension but rather expects it to lose its electoral relevance—due to religious decline.

2.3. Declining electoral relevance of traditional morality?

In the course of the twentieth century, Western Europe witnessed a tremendous decline in traditional Christian religiosity that affected both voters and political parties. While secularization in general is a complex process occurring on several interrelated levels (see Pickel, Reference Pickel2017; Stolz and Tanner, Reference Stolz and Tanner2019 for an overview), two of them are most often singled out by the religious cleavage studies as causing a theorized decline in the electoral relevance of moral traditionalism (Brooks et al., Reference Brooks, Nieuwbeerta and Manza2006; Minkenberg, Reference Minkenberg2010; Raymond, Reference Raymond2011). On the individual level, both believing and belonging, the key components of Christian religiosity, decreased significantly across Europe, with church attendance rates declining even faster than traditional Christian beliefs (Davie, Reference Davie1990; Norris and Inglehart, Reference Norris and Inglehart2004; Tromp et al., Reference Tromp, Pless and Houtman2020). On the social level, declining individual religiosity is typically accompanied by a decline in social significance of traditional Christian religion, i.e., religion losing its control over other societal spheres, including those of morality and politics (Bruce, Reference Bruce2002; Norris and Inglehart, Reference Norris and Inglehart2004).

As a result, West European countries experienced an observed shift toward moral progressiveness among both religious and non-religious individuals, with highly secularized countries also being the most morally progressive (Halman and Van Ingen, Reference Halman and Van Ingen2015). To compensate for the waning religious and traditionalist electorate, religious and conservative political parties in Western Europe are likely to take more progressive moral stances and appeal to a broader, less traditionalist audience, though such a change is likely to alienate their core morally traditionalist voters (Kalyvas, Reference Kalyvas1996; Euchner and Preidel, Reference Euchner and Preidel2018). Secularization of party programs is hence most likely in those countries where traditional Christian religion lost most of its social and political relevance.

Informed by secularization theory, then, studies on the religious cleavage theorize that religious decline has consequences not only for voters and political parties, as it also changes the motivation behind religious voting by weakening the role of religiously inspired voting motivesFootnote ¹ (see, for instance, Knutsen, Reference Knutsen2004; Minkenberg, Reference Minkenberg2010; Best, Reference Best2011; Raymond, Reference Raymond2011; Botterman and Hooghe, Reference Botterman and Hooghe2012; Goldberg, Reference Goldberg2014, Reference Goldberg2020). Two groups of studies address this vital proposition.

Studies in the first group analyze whether the electoral relevance of religion and associated morality has already declined or whether religion is still an important predictor of voting choice in Western Europe (Botterman and Hooghe, Reference Botterman and Hooghe2012; Goldberg, Reference Goldberg2014). In framing the research problem in this way, these studies focus on one time point only and do not incorporate religious decline into their models, even though they do refer explicitly to the latter process to account for the expected increased irrelevance of religious motives. While religiously inspired motives are found to be still powerful in predicting voting choice in Belgium (Botterman and Hooghe, Reference Botterman and Hooghe2012) and Switzerland (Goldberg, Reference Goldberg2014), the design of the aforementioned studies does not allow to tell, first, whether the predictive power of these motives indeed decreased over the years and, second, if so, whether religious decline actually accounts for it.

The second group of studies does incorporate temporal change by studying whether the link between religion and politics has weakened across Western Europe in recent decades (Knutsen, Reference Knutsen2004; Elff, Reference Elff2007; Van der Brug et al., Reference Van der Brug, Hobolt and De Vreese2009; Elff and Rossteutscher, Reference Elff and Rossteutscher2011; Raymond, Reference Raymond2011; Goldberg, Reference Goldberg2020). These studies do also explicitly refer to religious decline as the main driving force behind changes in the electoral relevance of religious motives but, ironically, do not incorporate religious decline into their models either. Instead, they interpret the observed changes over time as directly caused by religious decline.

The overview provided above illustrates that existing studies do not yet offer strong empirical evidence for the main implications of secularization theory for the religious cleavage. However, if this central proposition of the religious cleavage research is correct, then:

3.1. Data

To study what happens to the electoral relevance of moral traditionalism–progressiveness in Western Europe over time and with religious decline, we focus on individual moral traditionalism–progressiveness as a motive behind voting for political parties with morally traditionalist agendas. To do so, we require individual-level cross-sectional data with a time dimension, which allows us to not only detect a potential change over time, but also to test whether this change is explained through cross-sectional differences in the levels of contextual secularity (i.e., contexts affected by religious decline to a different degree). This way, we can test the hypothesis derived from the “cultural turn” literature for the electoral relevance of moral traditionalism in particular and not as a part of a broader cultural dimension. Contributing to the religious cleavage literature, we do not assume that the effect of religious decline equals that of time. Instead, we aim to identify whether the hypothesized change over time actually occurs due to varying levels of contextual secularity.

The data come from the European Values Study (EVS, 2021) featuring five waves (1981, 1990, 1999, 2008, 2017) and 20 West European countries: Austria, Belgium, Denmark, Finland, France, (West) Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Great Britain, and Northern Ireland.Footnote ² Respondents ineligible to vote due to age (i.e., below 18 years of age—0.1% of the initial sample) and followers of non-Christian religious traditions (i.e., Islam—0.91% and otherFootnote ³—2.19%) were excluded from the analysis. The sample in use amounts to 71,451 respondents from 79 contexts (i.e., country-year combinations) with an average of 916 respondents per context (see Appendix A for details).

3.2. Measurement

The dependent variable is a dummy for voting for religious or broadly conservative parties with morally traditionalist agendas (1) versus other parties (0). To measure religious/conservative voting, we used a standard EVS question on party preferences (i.e., “If there was a general election tomorrow, which party would you vote for?”) and divided the political parties preferred by the respondents into party families as suggested by the Manifesto Project Database (Volkens et al., Reference Volkens, Burst, Krause, Lehmann, Matthieß, Merz, Regel, Weßels and Zehnter2020). As discussed in the theory section, religious (i.e., Christian, Christian-Democratic, denominational) and mainline conservative parties are more likely, than parties from other families, to include morally traditionalist issues in their programs, and religious parties are, on average, more morally traditionalist than conservative ones (Van der Brug et al., Reference Van der Brug, Hobolt and De Vreese2009; Raymond, Reference Raymond2011; Euchner and Preidel, Reference Euchner and Preidel2018; Langsæther, Reference Langsæther2019). Appendix B demonstrates that this is indeed the case in our country-level sample and provides details of how religious and conservative party families feature favorable mentions of traditional morality in their programs compared to other party families in the period of 1981–2017. The list of parties in religious and conservative families is available in Appendix C. In line with the theory, we use “voting for religious/conservative parties versus the rest” as the dependent variable in the main analysis and provide the results of (less statistically conclusiveFootnote ⁴) robustness checks for religious and conservative voting separately in Appendix D.

The explanatory variables are individual moral traditionalism, time, and contextual secularity. Individual moral traditionalism is measured through a standard scale of religiously inspired moral attitudes (see, for instance, Langsæther, Reference Langsæther2019; Pless et al., Reference Pless, Tromp and Houtman2023). We use five questions on whether a respondent finds that abortion, homosexuality, euthanasia, divorce, and suicide “can always be justified, never be justified, or something in between” measured on a 10-point scale. To construct the scale, we standardize the five attitudinal variables and combine them with equal weights, assigning scores to those respondents who validly responded to at least four of the five questions. The resulting scale of moral traditionalism ranges from 0 (progressive) to 10 (traditionalist) and is highly reliable with an overall Cronbach's α of 0.82.Footnote ⁵

To measure time, we use the five waves of the EVS as a continuous predictor recoded to range from 1 to 5.

Contextual secularity is an indicator of how countries in the sample were affected by a decline in traditional Christian religion measured through its two key individual-level components that have been theorized to affect the electoral relevance of religiously inspired voting motives, i.e., believing and belonging.Footnote ⁶ For believing, we construct an additive scaleFootnote ⁷ for Christian beliefs that measures whether a respondent believes in God, heaven, hell, sin, and life after death (all the questions are binary). We then reverse the scale so that respondents with the highest scores are the most secular, and standardize it. To measure belonging, we standardize the religious participation variable (i.e., “apart from weddings, funerals, and christenings, about how often do you attend religious services these days?”) that originally ranges from “more than once a week” (1) to “never” (7). The correlation coefficient between believing and belonging is 0.62. Then we combine believing and belonging with equal weights into a general scale of traditional Christian religiosity–secularity that ranges from 0 (religious) to 10 (secular). Finally, we average individual-level scores of religiosity–secularity within each context (i.e., country-year) to compute contextual secularity scores. The highest values refer to the most secularized contexts, and the lowest values—to the most religious contexts.

Control variables are age, gender, and education (age when completed).Footnote ⁸ Descriptive statistics for all the variables in use can be found in Table 1.

Table 1. Descriptive statistics: main variables and scale components