1 Introducing Social Milieus to the Analysis of Social Integration

In contemporary welfare societies, social integration in terms of the inclusion of individuals and the relation between social groups (Grunow et al., this issue) was seemingly placed under strain recently owing to increased economic inequality and conflict. The precise nature of the current threats to social integration is under intense debate. Its most obvious indication is the rise of right-wing populism and the weakening of liberal democracy. A new cleavage, i.e., a cultural and political conflict tied to socioeconomic group inequalities, seems to have emerged between a liberal, cosmopolitan, educated urban middle class and an authoritarian, nationalist fuzzy coalition of the predominantly rural, male, working class and petty bourgeoisie, who are or feel relatively deprived by hegemonic liberalism. This cleavage has been described by different observers with varying nuances (see Hooghe and Marks 2018; Teney and Rupieper, this issue) but mostly referring to factions of the population that differ in their socioeconomic position and cultural values. For Germany, Reckwitz (2019) posited a tripartite division between an academic “new” and a traditional “old” middle class, and a low-skilled underprivileged class (see Kumkar and Schimank 2021 for a critical discussion).

These recent debates underscore the need for a better understanding of how social stratification overlaps with cultural values at the level of social groups. We propose the concept of social milieus to analyze the dynamics of social integration and its threats in contemporary welfare societies. Social milieus capture the divisions of society into large social groups that share socioeconomic positions and cultural values. We further presume (although we do not test this empirically) that social milieus cultivate their own modes of social integration within social milieus. The relationships between social milieus are characterized by a mixture of mutual ignorance, compromise, and (hegemonic) conflict—whereby some milieus tend to stipulate their modes of social integration on the entire society. Hence, following the conceptual discussion of social integration in the introductory chapter, we conceive social integration as multi-layered, with individuals being integrated into social milieus, and social milieus being integrated at the societal level. From this perspective, it becomes clear that social integration at the societal level can be neither achieved nor conceptualized simply as an upscaling of the mechanisms that govern within-milieu integration (i.e., trust, consensus, cooperation, conformity; see Grunow et al., this issue). Instead, it additionally has to account for the heterogeneity of milieu-specific modes of social integration, e.g., by institutionalized and cultivated forms of conflict as well as compromising, mutual understanding and recognition.

In this article, we propose the first steps toward a concept of social milieus and a framework for analyzing social integration from a milieu perspective. In the following, we first provide a literature review on the concept of social milieus in stratification research as well as on the closely related research strands on sociocultural cleavages and values (Sect. 2). Based on this, we provide theoretical considerations for a concept of social milieus and its research potentials for analyzing social integration (Sect. 3). Next, we give an example of how the concept of social milieus can be operationalized by Latent Class Analysis (LCA) using data from the German subsample of the European Social Survey (ESS) (Sect. 4) and present an empirical typology of social milieus in Germany (Sect. 5). In the concluding Sect. 6 we summarize the findings and limitations and provide an outlook on future research avenues.

2 State of the Art: Social Milieus at the Intersection of Social Stratification and Cultural Conflict

The sociological concept of social milieus was introduced to sociology by Durkheim (1982) for studying the moral integration of social groups. However, it has not become a well-established concept in the international sociological debate for three reasons.Footnote 1 First, the term “milieu” is mostly translated as “environment” (Durkheim 1982, p. 135) or used vaguely as a nontechnical term. Second, the resembling concept of “social classes” dominates the international discourse. Social class (as distinct from occupational class concepts) refers to social groups that are marked by a specific “conduct of life” similar to (feudal) “estates” (“ständische Lebensführung”) and “social closure” in terms of social networks and mobility boundaries (Weber 1978, p. 43, p. 341). A broad range of social class analyses could also be labeled milieu studies, for example, the analyses of class and (sub-)culture of the Birmingham School (Thompson 1964) or the class model based on the work of Bourdieu (1984; Savage et al. 2013). Third, the concept of social milieus had its heyday during the 1990s in a German sociological debate on “individualization” and “de-structuring” (Beck 1992) but soon lost its importance in the face of increasing economic inequalities. It has been revived recently, though, for the analysis of threats to social integration (Vehrkamp and Wegschaider 2017; El-Menouar 2021).

In this chapter, we review the literature on social milieus and highlight that the concept goes beyond the notion of socioeconomic classes by adding cultural attributes (Sect. 2.1). We then extend the particularly German discourse on social milieus to the ongoing international debate on sociocultural cleavages (Sect. 2.2) and, as the conceptualization of the cultural dimension of social milieus and cleavages remains vague, to a social psychological concept of values (Sect. 2.3).

2.1 Conceptualizations of Social Milieus

In the 1920s and 1930s, a specific German conception of “milieus” that focused on the “world of everyday life” (“Lebenswelt”) and differences in cultural “lifestyles” came to considerable prominence (Grathoff 1995). After World War II, however, research postulating that these cultural aspects are strongly affected by socioeconomic stratification dominated the German sociological debate (e.g., Dahrendorf 1959). In the 1980s, the paradigm of class structuration was questioned against the backdrop of economic growth, declining economic inequalities, the rising welfare state, educational expansion, and cultural modernization. The Anglo-American literature noticed a “fragmentation of stratification” (Clark and Lipset 1991, p. 397) and, concomitantly, a growing importance of the cultural dimension (Hall 1996). In Germany, Beck (1992) posited a process of “individualization” of social inequality. Socioeconomic positions and living conditions were considered to have lost their relevance to everyday life and cultural lifestyles so that collective class cultures, identities, and conflicts had vanished.

The concept of social milieus has been (re-)introduced into this debate as an intermediate perspective: it claims that individualization has not completely eradicated social groups but that these groups have become more pluralized and latent. Several scholars have developed this idea under the label of “social milieus” (instead of social class), with varying emphasis on the relationship between socioeconomic positions and culture. Hradil (1983) introduced social milieus as a meso-level concept mediating structural living conditions by subjective situations. Milieus were defined as social groups sharing similar socioeconomic positions and lifestyles. Schulze (2000) focused on cultural lifestyles as schemes of everyday experience and cultural consumption, whereby educational levels served as a stratifying dimension, but the hierarchical socioeconomic structure was not considered as constitutive for social milieus.

Vester et al. (2001) have provided the most elaborate theoretical and empirical account of social milieus so far. They employed the qualitative informed milieu typology of the Sinus® Institute (Flaig et al. 1994) as a heuristic tool in the absence of an alternative empirical operationalization. The Sinus® institute grouped individuals with similar life goals, lifestyles, values, attitudes, aesthetical preferences, and practices of everyday life into social milieus. These were then depicted on a vertical axis referring to social stratification and a horizontal axis ranging from traditional to modern values. Socioeconomic positions were considered only to the extent that they are formative for the self-conception of the members of a milieu. Vester et al. (2001) delivered a theoretical foundation of social milieus based on Bourdieu and the tradition of the Birmingham school in class analysis. Social milieus were characterized in terms of a specific “habitus,” their everyday ways of coping with their stratified positions. Two dividing lines were identified on the vertical socioeconomic axis that correspond to symbolic boundaries: the members of the skilled working class milieus and petty bourgeoisie demarcate themselves from the lower social classes by drawing a boundary of “respectability,” thereby claiming to belong to the “decent” middle classes, as opposed to both the lower classes, which are perceived as “underserving,” and the upper classes, which are perceived as “snobby” or even “decadent.” The upper class milieus demarcate themselves from the middle and lower ranks by drawing a boundary of “distinction,” considering themselves as culturally “distinguished” from “ordinary” people (see Vester et al. 2001, p. 26). The horizontal axis was interpreted as an axis of modernization with traditional values of conservation, security, and conformity on the one side and modern values oriented toward openness to change and exploration of new lifestyles on the other side. Vester et al. (2001, p. 427) provided a detailed empirical account of various modes of within-milieu social integration (termed “social cohesion”). They furthermore argued that social milieus need to be clearly distinguished from political camps, although the latter can be understood as political coalitions between social milieus.

Recently, Reckwitz (2019) used the Sinus® milieus for differentiating the conflicting “new” and “old” middle classes he identified. However, the use of the Sinus® milieu typology is problematic as the Sinus® institute does not reveal the clustering algorithm, making proper scientific research difficult (Sachweh 2021). Thus, a contemporary and scientifically transparent model for operationalizing social milieus based on large-scale survey data is still lacking.

Several approaches are closely related to our understanding of social milieus. Otte (2005) created a theoretically informed “integrative typology” of “conduct of life,” based on his own survey instrument for use in large-scale surveys. Rössel and Just (2014, p. 209) emphasized the importance of social networks (in terms of social interactions associated with similarities between persons) for social milieus. The More in Common study described six milieus along two axes: orientation toward social cohesion and modernization vs. traditionalism (Krause and Gagné 2019). El-Menouar (2021) identified seven “value milieus” based on Schwartz’ (1992) basic human values and personality traits. Other approaches use the milieu concept in a more issue-related way. For example, Neugebauer (2007) clustered nine “political milieus” based on political attitudes, Decker and Brähler (2016) focused on right-wing extremism, and Kösters and Jandura (2018) on political communication and social integration. These typologies are very informative of how the population clusters into certain groups. However, they are mostly restricted to the cultural dimension or even particular issue-related aspects of culture and treat socioeconomic stratification merely as a correlate.

Summing up, the concept of social milieus allows for an intuitively grounded understanding of the ways in which societies are clustered into social groups. The most elaborate theoretical account on social milieus by Vester et al. (2001) pronounces the importance of cultural lifestyles or values and social stratification. The empirical milieu approaches reviewed above, however, often remain nontransparent and/or lack theoretical foundation. Moreover, milieus are in danger of being eventually reduced to simple aggregations of socioeconomic and—or even only—cultural characteristics without taking demarcation processes and conflicts between milieus into account. As a consequence, the existing concepts are unsatisfactory for a robust analysis of social milieus and its implications for social integration. Therefore, we open up the perspective on social milieus and review the international debate on sociocultural cleavages in the following section.

2.2 Research on Sociocultural Cleavages

Within political sociology, the debate on social integration changed considerably in the 1960s when structural-functionalist theory, mainly represented by Parsons, faded in favor of conflict theory (Dahrendorf 1959). The so-called “cleavage theory” put forward by Lipset and Rokkan (1967) argued that Parsons’ (1971) “integrative subsystem” can be further differentiated. In contrast to Parsons’ claim that common value orientations enable social integration (see Grunow et al., this issue), they emphasized the importance of “sociocultural cleavages” “which tend to polarize the politics of any given system” (Lipset and Rokkan 1967, p. 6).Footnote 2 Four historically evolved cleavages, which led to the formation of corresponding political parties, were distinguished: central national culture vs. ethnic subcultures, state vs. church, agriculture vs. industry, and capital vs. labor. In transferring this line of research to Germany, Pappi and Laumann (1974, p. 160) highlighted the dimension of value orientations by arguing that “cultural interpretations” mediate the impact that conflicts of interest exert on political attitudes.

The focus on a value dimension of sociocultural cleavages pre-empts a discourse in the political sciences parallel to the sociological debate on individualization and de-structuration (Kriesi 1998). Some scholars postulated a decline in the structuring of political behavior by the “old” cleavages. Soon, so-called “new cleavages” were addressed. These reflected the value change from traditional and materialistic values of economic security and self-enhancement toward post-materialistic values of self-direction and self-transcendence (Inglehart 1971). Taking class differences into account, Kriesi (1998) found a “new value cleavage” between two segments of the middle class similar to Reckwitz’ (2019) distinction between the “old” and “new” middle classes: the older segment of managers and a newly emerging segment of sociocultural professionals. Following Kitschelt’s (1994) two-dimensional scheme of (political) value orientations, the former segment holds right-wing authoritarian values, whereas sociocultural professionals exhibit left-wing, libertarian, post-materialistic, universalistic values of individual autonomy and (global) egalitarianism. Kriesi (1998) and Kitschelt (1994) argued that this value cleavage primarily derives from different “work logics” (Oesch 2012).

Regarding globalization, another cleavage was observed between the “new” middle class as the cosmopolitan “winners” of globalization and the working class as “losers” who worked in protected sectors, developed a national or communitarian identity and turned to the radical right (Kriesi 1998; Kriesi et al. 2006; see Teney and Rupieper, this issue, for a detailed discussion). It was argued that the right-wing movements emerging in the 1990s were a backlash against the social movements of the new left occurring in the 1970s (Bornschier 2010; Oesch 2012). Ford and Jennings (2020) held that in the wake of the structural changes of the twenty-first century—(further) expansion of higher education, mass migration, aging, and geographical segregation—cleavages along class, ethnicity, generation, and the urban–rural divide are pronounced. However, Teney and Rupieper (this issue) found no clear sign of an increasing conflict regarding globalization. The “embedding hypothesis” (Kriesi et al. 2006), moreover, states that the new cleavages are still shaped by traditional ones. Still, two dimensions, the economic and the cultural dimension, were identified (Kriesi et al. 2006).

In sum, the cleavage theory operates, just as the milieu approaches, with a socioeconomic and a cultural dimension and has its obvious strength in taking major societal conflicts into account. However, inasmuch as the cleavage theory—reasonably—moved away from the theoretical foundation of structural-functionalism, the identification of (old and new) cleavages conveys the danger of becoming a mere empirical enumeration (Franklin 2010). Still, there is no systematical connection to the study of social milieus (see Kitschelt 1994, p. 18 f.), with the exception of Lepsius’ 1993 concept of “socio-moral milieus,” which is frequently employed in historical analysis (Lösche 2010). Sociocultural cleavages highlight the dividing nature of fundamental cultural conflicts. Yet, the nature of the various cleavages remains unclear, ranging from political to cultural value conflicts.

2.3 Conceptualizing Values

Both milieu and cleavage approaches have identified a cultural dimension of values, lifestyles, attitudes, and practices. However, a profound theoretical and empirical conception of the cultural dimension is missing. We focus on values as probably the most crucial cultural variable for our research interest. First, values have been considered a central element in both milieu and cleavage theory. Second, the analysis of values as general individual differences allows us to understand a wide range of different issue-related attitudes and behaviors (Schwartz 2015).Footnote 3 Third, values can be compatible or conflicting with one another and thus provide a solid foundation for the analysis of cultural differences, conflicts, and social integration.

The most eminent approach to values is the theory of basic human values developed by Schwartz (1992). Values are defined as “concepts or beliefs” about “desirable end states” that “guide selection or evaluation of behavior and events” (Schwartz 1992, p. 4). A major advantage over other value theories—such as Inglehart’s (1971) theory of post-materialistic value change and its advancements (Inglehart and Welzel 2005) or moral foundations theory (Haidt and Graham 2007)—is the exhaustive account of human values (see Bilsky et al. 2010). The values are arranged in a quasi-circumplex structure (see Fig. 1): adjacent values are most compatible whereas opposing values are conflicting. On a group level, people tend to dislike groups that are perceived to endorse values conflicting with their own groups’ values (Grigoryan et al. 2023).

Fig. 1
figure 1

Schwartz’ basic human values. (Source: Magun et al. 2016)

Schwartz proposed a basic division into ten values (e.g., universalism, tradition, power, self-direction; see the inner circle in Fig. 1) and a broader division into four higher-order values (see the ring around the inner circle).Footnote 4 Just like the ten values, the higher-order values on the opposite sites of the quasi-circumplex structure are conflicting: self-enhancement vs. self-transcendence and openness to change (hereafter “openness”) vs. conservation (Schwartz 1992). On an even higher level of abstraction, each pair of adjacent higher-order values can be described as a value focus (Schwartz et al. 2012; Magun et al. 2016): the social focus (combining self-transcendence and conservation) opposes the personal focus (combining openness and self-enhancement), and the growth focus (combining self-transcendence and openness) opposes the protection focus (combining conservation and self-enhancement). Schwartz (1992) pointed out the importance of individuals’ value profiles, as individual behavior is guided by the set of all values. Magun et al. (2016) used LCA to group individuals by similarities in their value profiles, identifying five value classes with distinct value profiles for Europe.

Summing up, we consider the concept of Schwartz’ basic human values to be the most appropriate for conceptualizing the cultural dimension of social milieus. It is linked to the cleavage approach as (potentially) conflicting values are identified. Yet, the three strands of milieu, cleavage, and value research have not been connected so far. The next sections provide a theoretical and empirical framework for this project.

3 A Theoretical Framework for Analyzing Social Milieus and Social Integration

In this section we build on the literature reviewed above and provide a more in-depth discussion of the theoretical foundations of social milieus and a framework for analyzing social integration from the perspective of social milieus. We understand this framework as a first step toward a full-fledged theory of social milieus and their contribution to social integration. We start with the notion of social milieus as large latent groups that share similar combinations of socioeconomic and cultural characteristics (Sect. 3.1) followed by a discussion of the two dimensions of social milieus: the dimension of social stratification (Sect. 3.2) and the cultural dimension (Sect. 3.3). We then discuss the theoretical relationship between the two dimensions (Sect. 3.4), and finally the analysis of social integration from a milieu perspective (Sect. 3.5).

3.1 Social Milieus as Large Latent Groups

Following the discourse on social milieus reviewed in Sect. 2.1, we define social milieus as large latent groups with similar socioeconomic positions and cultural values. In a topological model of the population, all social milieus together constitute a “landscape” or “social space.” Hence, social milieus cover certain areas of this space and, subsequently, have meaningful distances to one another. The dimensions of this space are a vertical dimension of social stratification and a horizontal dimension of cultural values. We conceive both dimensions as conflictual dimensions in which conflicts of superiority and power are involved. Whereas values compete for dominance and hegemony, the hierarchy of socioeconomic positions is structurally grounded in the system of socially stratified resources and resulting life chances.

As socioeconomic positions and cultural values are meaningfully combined in social milieus, they can be considered as collectivities. They emerge and develop historically, often in conjunction with cultural and/or political organizations (as also highlighted in the sociocultural cleavage literature and historical research on “socio-moral” milieus). As such, not all but only a few of the possible combinations of socioeconomic positions and cultural value profiles are collectively cultivated as social milieus—not the least due to processes of collective conflicts and mutual distinctions. Individuals may be assigned or feel attached to one or more social milieus, depending on the individual’s personal values and socioeconomic positions, as resulting from their socialization, life course, and social networks. Hence, social milieus can be straightforwardly detected as clusters of individuals’ combinations of socioeconomic positions and cultural values, because they are collectivities that shape individuals’ values within certain socioeconomic positions.

Social milieus are typically conceptualized for national populations as they emerge and develop mainly within national historical contexts. Zooming into specific social milieus, one may discover more specific sub-milieus. For Germany, the division between West and East Germany and their different historical traditions may be considered important, so that both parts of the country may have their own social milieus (Vester et al. 1995). Moreover, ethnic minorities, religious groups, youth, or other “communities” may form their own (sub-)milieus, given their respective cultural traditions and their (varying) degrees of group segregation. All these variations become particularly relevant if research interests are geared toward differences in lifestyles, group identifications, or groups with particularly dense social networks (Rössel and Just 2014). Yet, all these (sub-)milieus would still remain latent groups. As such, they have to be distinguished from manifest and much smaller social groups (e.g., social scenes, neighborhood groups). The concept of “macro” social milieus that we propose here identifies more general groups with latent similarities, which indeed result in higher propensities for milieu homophily in the social networks, including couples and families, neighborhoods, etc.

3.2 The Socioeconomic Stratification Dimension of Social Milieus

Members of a given social milieu share similar socioeconomic positions.Footnote 5 We argue for an explicit incorporation of social stratification into the conceptualization of social milieus for three reasons: First, socioeconomic positions are crucial determinants of life chances and opportunities for social contact with other socioeconomic groups, and thus structure the opportunities for individual and collective action. They divide individuals structurally, e.g., via social segregations or resource constraints. Second, they thereby shape cultural values, although not in a linear way (see below, 3.4). Third, the vertical dimension of social stratification is also reflected and enacted by drawing symbolic boundaries of “respectability” and “distinction” between social milieus (Vester et al. 2001, p. 26).

3.3 The Cultural Dimension of Social Milieus

The cultural dimension of social milieus leaves us with a range of open questions. What is the scope of the cultural dimension (lifestyles, life goals, attitudes, practices, or values) and how can these be systematized? As mentioned, we choose values as the core focus of our conceptualization of the cultural dimension of social milieus. We refer to Schwartz’ theory of basic human values because it provides an exhaustive, universal set of values that are arranged in a circular structure and range from high compatibility of adjacent values to a potential conflict between opposing values.Footnote 6 The circular value structure allows for the detection of cultural cleavages in society without presupposing one particular value conflict. Rather, it conveys that various value conflicts are possible.

Regarding sociocultural conflicts, the most relevant values are seemingly self-transcendence and self-direction on the one hand and conservation and power on the other. For example, attitudes toward immigrants have been negatively predicted by security and conformity and positively predicted by universalism and self-direction (Schwartz 2015). Egalitarian gender attitudes have been predicted positively by universalism, self-direction, and benevolence, and negatively by tradition and power. Environmentally friendly behavior, as well as prosocial behavior, have been predicted positively by universalism and benevolence, and negatively by power (Schwartz 2015).

Interestingly, the literature on cleavages and conflicts as well as the Sinus® milieus suggest a similar dominant opposition. The cultural axis of the Sinus® milieus (Barth et al. 2018, p. 11) provides references to Schwartz values with “tradition” and “conserving” (conservation values) versus “exploring” and “crossing borders” (openness) at the extreme poles. The intermediate range of the cultural axis in the Sinus® milieus is characterized by a mix of “self-enhancement” values, i.e., achievement and power, and openness values such as hedonism and self-direction. The axis does not include references to self-transcendence. In cleavage theories, the cultural conflict dimensions regularly show a “traditional” pole with often direct reference to conservation values (tradition, conformity, and security), sometimes framed as “authoritarian.” The opposing pole found in many cleavage approaches (termed, for example, libertarian-universalistic or cultural liberalist) covers the entire growth focus (see Fig. 1, above). This indicates a potential for more fine-tuned differentiations. In sum, Schwartz’ basic human values closely connect to opposing poles of the cultural dimension employed in the Sinus® milieus and seem to reflect a variety of conflicting oppositions identified by cleavage theories.

3.4 The Relationship Between Stratification and Culture

Empirically, in Germany, education and income are positively related to self-transcendence and self-enhancement (Meuleman et al. 2012). Furthermore, education is positively (negatively) correlated with openness (conservation). However, an advantage of the concept of social milieus lies in a more flexible and nuanced analysis of the relationship between socioeconomic positions and cultural values than correlations reveal. Some social milieus, for instance, might hold very well-defined values but expand along the socioeconomic axis, indicating that the former are more relevant. For other social milieus the opposite might apply, i.e., similarities in socioeconomic positions are predominant and accompanied by greater within-milieu heterogeneity in values. Moreover, some milieus might be small but very specific in their combined socioeconomic and value profile; others might be large and less well differentiated.

Although these features are typically taken as “descriptive” or “explorative”, they are quite telling in theoretical terms. The debate on whether socioeconomic or cultural determinants are more relevant for explaining populist voting typically assumes (unless interactions are specified) that “stratification” and “culture” operate uniformly across the range of socioeconomic positions and across the space of cultural values or attitudes. The concept of social milieus, instead, assumes that the relationship between socioeconomic inequalities and culture is more complex and therefore requires a typological model. Two theoretical arguments can be made here:

First, we assume that there is a “real-world” sorting mechanism behind the clustering of socioeconomic positions and cultural values. These sorting processes can be understood as a combination of dividing forces between social milieus that separate them along socioeconomic factors and values (involving spatial segregation into regions and neighborhoods, institutional segregation into schools and workplaces, lifestyle segregation based on economic costs, symbolic boundary drawing, etc.). In addition, cohesive forces within social milieus exert a certain pressure of homogenization, owing to processes of norm conformity, socialization, imitation, and contagions, and owing to socioeconomic closure and shared material interests. These divides between social milieus are not necessarily, but potentially and often explicitly, conflictual. Accordingly, the demarcations between social milieus may be reinforced by symbolic boundaries and distinctions against other milieus. Once social milieus have emerged, they reproduce themselves via the structuration of life chances and mobility, and via processes of value transmissions and socialization in families, neighborhoods, or among peers. It should be noted that these sorting mechanisms are counteracted by cross-cutting or boundary-blurring forces, such as social mobility, cross-class families, bridging social ties, and mixing of social groups, and thus produce merely latent group structures.

Second, a specific feature of the concept of social milieus is the possibility that the very same socioeconomic position might bring to existence two or more distinct “class cultures”—i.e., social milieus. This possibility objects to class theories that assume that a certain class position will always bring about exactly one corresponding class culture. This also pertains to approaches in the line of Bourdieu’s (1984) work and the assumption of homology between structure and habitus, which also underlies the theory of social milieus by Vester et al. (2001). The concept of social milieus, in our understanding, allows for the evolution of conflicting cultural responses (at the level of social groups) to the very same socioeconomic positions. The historically most striking case of such dual class cultures is the coexistence of “conservative” (in many European countries: catholic) and “social-democratic” working class milieus, which is more recently echoed by the divides between the “authoritarian” and the more social-democratic working classes. Other examples pertain to the distinctions between the economic and the cultural fractions of the bourgeoisie. We suppose that the emergence of different milieus from similar socioeconomic positions can be understood as alternative responses to challenges that are inscribed into a given socioeconomic position. Although these shape, to some extent, cultural values, they are still open to alternative ways of sense-making, leading to historical evolutions of different social milieus based on similar socioeconomic positions.

3.5 Social Integration—From a Perspective of Social Milieus

In this section, we provide some further theoretical considerations on the concept of social milieus and its implications for studying social integration as a multi-layered structure (see Grunow et al., this issue). Although we do not test these empirically, we deem them useful for the analysis of social integration.

We frame social milieus in a conflict theoretical perspective, assuming that social milieus are groups at the intersection of socioeconomic and cultural conflicts. These conflicts, and thus the demarcation lines between social milieus, are construed as latent structures. The clustering of social milieus is, as described above, the aggregated result of sorting and socialization processes that unfold at the intersection of socioeconomic stratification and cultural conflicts, shaped by collective organizations. There are, of course, counteracting forces, constantly shaking up the existing milieu structures. Hence, the degree to which social milieus are separated from one another, their number and structuring (the “landscape” of social milieus), and the degree to which individuals are affiliated and attached to particular social milieus, all vary empirically. These variations are of particular interest for studying the social integration of societies. From a social milieu perspective, social integration is a multi-layered structure, with individuals embedded in social milieus and social milieus embedded in society (see also Grunow et al., this issue).

Individuals can be more or less strongly integrated into one or more social milieus. Social milieu integration provides individuals with a sense of belonging, with resonating environments of others who share similar socioeconomic conditions and values. For sure, individuals move across various fields or life domains, which are populated by members from different milieus. It would thus be misleading to assume that individuals live their lives completely within just one social milieu (Otte and Rössel 2011). However, the contrary idea of a completely individualized life course turned out to be empirically misleading as well (e.g., Lux 2011). Individuals are typically surrounded by and embedded in groups of similar others to which they feel attached or at least acquainted. Given the empirical findings that social mobility is rarely far-ranging, and that strong value changes within individual lives are equally rare, the milieus of origin shape individuals’ life chances and values to a considerable degree. To exemplify this, consider that individuals raised in rural lower class milieus will most likely not become fully integrated members of urban academic milieus and vice versa. The probabilities of individual social mobility and value change are, of course, highly dependent on societal structures of equality of opportunities and structural value change, and can therefore vary across time and space.

Social milieus vary in the degree and mode of within-milieu social integration, or social cohesion.Footnote 7 Some social milieus are more individualized than others, in terms of imposing weaker norms and less norm conformity on their members than more traditional milieus. Yet, individualized social milieus may still be highly encapsulated and separated from traditional milieus. This is to say, more generally, that some milieus may be more distinctive than others, and may draw more distinctive boundaries against certain other milieus. Likewise, social milieus vary in the modes of within-milieu social integration. These varying modes of cohesion might be in conflict with other modes of social cohesion prevalent in other social milieus. Regarding the debates on new cleavages, e.g., connected to right-wing populism, one may argue that modes of social cohesion that embrace traditional hierarchies on the basis of paternalistic relations (e.g., employer–employee relations, anti-egalitarian gender roles, nationalistic cultures) may be more capable of bridging socioeconomic distances than modes of social cohesion that embrace individualistic freedom and human rights but rely heavily on competitive markets. This might be a reason why and how right-wing populism manages to mobilize milieus across socioeconomic classes, whereas the social milieus supporting liberal cultural values fail to do so.

This leads to the societal perspective on the interrelations between social milieus. Distinguishing social integration within and between social milieus, we argue, is important because different mechanisms are at stake. Within-milieu integration operates through commonalities and similarities in socioeconomic living conditions and values, providing the ground for trust, conformity, consensus, and cooperation (see Grunow et al., this issue) between members of a given milieu. Social integration between social milieus, however, can be neither achieved nor conceptualized by simply upscaling the mechanism of within-milieu integration to the societal level. Rather, it additionally depends on the structures and institutions that shape and regulate socioeconomic inequalities and cultural conflicts, and in particular the relations between social milieus. The degree to which societies are able to integrate or even bridge social milieus, or the degree to which they fall apart into distinct or even conflicting social milieus, varies across time and space. Social integration, in terms of societal integration of social milieus, may be accomplished by fostering individual mobility and/or interactions across social milieu divides, or by arrangements of compromising and balancing the material interests and cultural values between different milieus. In times of rapid social change, new social milieus may emerge—as was the case during the 1960s and 1970s, when educational and social mobility was accompanied by cultural value changes, giving birth to the so-called “new social movements” and “new social milieus” (Vester et al. 2001, pp. 253–369). In times of stability and growth, social milieus become more latent, permeable, and fuzzy, allowing individuals to cross different social milieus more easily in different life domains or periods in the life course. In times of increased economic polarization, declining (upward) mobility, and increased cultural conflicts, the latent conflict structures of social milieus become more salient. It seems that this situation characterizes our present-day welfare societies.

4 Empirical Model

In this section, we present an empirical typology of social milieus based on the theoretical framework provided above. The typology includes the socioeconomic and cultural dimension of our milieu definition as its main elements and identifies milieus as large latent groups probabilistically using LCA. The model can be readily applied to large-scale survey data, is open to a wide range of applications, and can be adapted for specific research interests.

4.1 Data and Operationalization

For our empirical analysis, we use the German subsample of the European Social Survey from 2016 (ESS 8; N = 2470 after case-wise deletion of missing values). To correct for different selection propensities of respondents and to take the population structure (regarding gender, age, education, and region) into account, we use post-stratification weights. To operationalize the socioeconomic dimension, we employ education and household income as ordinal indicators, representing socioeconomic status (Ganzeboom et al. 1992). Education is measured as the highest degree of formal education and categorized into three groups: low (no degree, or lower secondary school, i.e., “Hauptschule”), intermediate (intermediate secondary school, i.e., “Realschule”), and high (upper secondary school, i.e., “Abitur” or “Fachhochschulreife.”) Household income is measured as total net household income quintiles and equalized across households by dividing it by the square root of household size (OECD 2020). To operationalize the cultural dimension of social milieus, we employ Schwartz’ basic human values, which are assessed by the 21-item Portrait Value Questionnaire (PVQ-21, see Tab. S1 in the Online Appendix). Participants are asked to rate how much a fictional person that holds a specific value is like them. An example item for self-transcendence is: “It is important to her/him to listen to people who are different from her/him. Even when she/he disagrees with them, she/he still wants to understand them.” The responses ranged on a six-point scale from “very much like me” to “not like me at all.” The scores were person-centered (i.e., ipsatized) by subtracting the person’s mean of the 21 items from each response in order to obtain the relative importance of each value (Schwartz 2020).

4.2 Method: Latent Class Analysis

We conduct an LCA (Hagenaars and McCutcheon 2002; Masyn 2013) using income, education, and the 21 person-centered value items as indicators. Like cluster analysis, LCA clusters individuals according to their response profiles. The method has been used as a powerful tool for the analysis of Bourdieu’s social space (Waitkus and Groh-Samberg 2019), social classes (Savage et al. 2013), and the relationship between social milieus and social cohesion (Kmetty et al. 2018). In contrast to methods such as cluster analysis or multidimensional scaling, LCA is model based and can be integrated into the generalized framework of structural equation modeling. Most important for our theoretical understanding of social milieus, LCA is a probabilistic model, assigning a certain probability to every individual for belonging to each of the clusters or milieus.

The LCA is conducted in Latent GOLD® 6.0.Footnote 8 To decide on the number of classes, we consulted several information criteria (see Tab. S2 in the Online Appendix) and assessed the candidates with a good fit based on theoretical grounds, as recommended by Nylund-Gibson and Choi (2018). This results in a nine-class solution as a parsimonious model for analyzing the general milieu landscape. An alternative 13-class solution may be consulted for more specific milieu differentiations in future research (see Fig. S1 in the Online Appendix).

5 Empirical Findings

The LCA provides 1) the sizes or percentage shares of the social milieus and 2) milieu-specific estimates of the indicators: a) estimated proportions of education and income as categorical indicators and b) means of the 21 person-centered value items. In addition to the milieu indicators, we report socio-demographic information on age, sex, and region (which did not enter the LCA). The LCA output is shown in Tab. 1. To ease interpretation, the milieu-specific means of the 21 person-centered value items are aggregated to the four higher-order values by calculating means (see Tab. S1 in the Online Appendix for all 21 value items).

Table 1 A model of social milieus: Latent Class Analysis of socioeconomic position and basic human values

For the purposes of presentation, similar to Magun et al. (2016), we condense the information given in Tab. 1 by plotting the positions of the milieus on the socioeconomic and value dimensions in bubble charts (see Fig. 2). The sizes of the bubbles correspond to the sizes of the social milieus. Education and income are condensed into an axis of the socioeconomic position by treating them as continuous variables so that the milieu-specific means can be calculated and transformed onto a common scale with a minimum of zero and a maximum of one, and then averaged. The four higher-order values are condensed into two value axes by subtracting openness from conservation and self-transcendence from self-enhancement.

Fig. 2
figure 2

A new model of social milieus: Latent Class Analysis of socioeconomic position and basic human values. a socioeconomic position and value axis: conservation vs. openness. b socioeconomic position and value axis: self-enhancement vs. self-transcendence. c value axes: conservation vs. openness and self-enhancement vs. self-transcendence. (Source: ESS8, 2016, weighted data, n = 2470, own calculations)

Each bubble chart in Fig. 2 represents two axes of the social space. Panel A plots the socioeconomic axis against the conservation vs. openness axis. This graph resembles the depiction of the Sinus® milieus. In Panel B, the socioeconomic axis is plotted against the value axis ranging from self-enhancement to self-transcendence, which is an addition to the Sinus® typology. Panel C plots both value axes against each other and thus represents the positions of the milieus on the Schwartz value circle (see Fig. 1). Each milieu is assigned a shade of gray indicating its relative value focus, i.e., its position on both value axes relative to the other milieus. For example, we assign a personal value focus to milieu 3, because it endorses openness and self-enhancement more strongly than other milieus. If a milieu holds average values on one value axis, we name its focus after the higher-order value it tends to on the other value axis (e.g., milieu 5 has a self-enhancement focus). The socioeconomic axis is divided into three strata corresponding to the lower, middle, and upper third of the analytically possible range.

At this point, we refrain from giving names to the milieus. This procedure requires comprehensive analyses in terms of criterion validity, i.e., systematic milieu differences in sociodemographic characteristics, attitudes, and practices (Flaig et al. 1994). Instead, we number the milieus according to their socioeconomic status, classify them into lower, middle, and upper socioeconomic strata, and mark them according to their value foci.

In line with previous findings (Meuleman et al. 2012), bivariate correlations (see Tab. S3 in the Online Appendix) show that the socioeconomic position of the respondents correlates positively with openness (education: r = 0.067; income: r = 0.069), self-enhancement (education: r = 0.152; income: r = 0.093), and self-transcendence (education: r = 0.118), and negatively with conservation (education: r = −0.248; income: r = −0.144). Our milieu typology reflects these correlations and additionally uncovers heterogeneity in terms of group-specific constellations of socioeconomic positions and value profiles.

Figure 2 shows that the milieus are clearly stratified by socioeconomic position. Although the boundaries are somewhat arbitrary, roughly, one upper class milieu (1), two upper middle class milieus (2 and 3), two middle class milieus (4 and 5), three lower middle class milieus (6, 7, and 8), and one lower class milieu (9) can be identified.Footnote 9 In every socioeconomic stratum, milieus with different value profiles are present. Interestingly, the upper-class milieu (1; size: 17%) is the most average milieu in terms of its values (see Panel C in Fig. 2). In contrast, the two upper middle-class milieus (2 and 3; 7% and 8%) are endorsing high openness but differ strongly from each other on the self-enhancement vs. self-transcendence axis. The two middle-class milieus (4 and 5; 10% and 4%) are placed centrally between conservation and openness, but—just as their upper middle-class counterparts (2 and 3)—on the opposing ends of the self-enhancement vs. self-transcendence axis. In the lower middle class, we find three milieus (6, 7, and 8; 10%, 8%, and 17%), which again differ in their value profiles. Milieus 6 and 8 are found on opposing ends of the self-enhancement vs. self-transcendence axis, with milieu 6 also endorsing openness more than milieu 8. Milieu 7 is the most conservative of all milieus, but holds self-transcendence values almost as high as milieu 6. The lower class milieu 9 (19%) is the second most conservative, with a similar position on the self-transcendence vs. self-enhancement axis as milieus 6 and 7.

Regarding value foci, we find milieus with a social focus (milieus 4, 7, 9), a growth focus (milieus 2 and 6), a personal focus (milieu 3), and a self-enhancement focus (milieus 5, 8, and, to a lesser degree, milieu 1). Conflicts between milieus can be expected to emerge between opposing value foci, and coalitions across social stratification may be formed along value foci. As an example, the milieus with a growth focus, milieus 2 and 6 from the upper-middle and the lower middle class, might build a coalition in opposition to the self-enhancement milieus (1, 5, and 8) from the upper, middle, and lower middle class. Similarly, the only milieu with a personal focus (3) from the upper middle class might oppose a coalition of milieus with a social focus (4, 7, and 9) from the middle, lower middle, and the lower class.

Some of the milieus we detect are similar to the Sinus® milieus, such as milieu 2, which resembles the Postmaterialistic Sinus® milieu. By considering socioeconomic positions and a second value axis, we furthermore detect milieus that are not represented in the Sinus® typology. An example is the lower middle class milieu (8), which has some similarities with the adaptive-pragmatic and the consumer hedonistic Sinus® milieu, but its self-enhancement focus marks it as a separate milieu.

Our milieu typology can be compared with Reckwitz’ (2019) distinction between a “new” and an “old” middle class. In our typology, however, none of the milieus holds a protection focus that is a central characteristic of the “old” middle class. Although milieu 5 can be interpreted as an “old” middle class milieu, it does not endorse conservation strongly. Milieu 8 is similar to milieu 5 regarding its self-enhancement focus, but has too low a level of education and income to be considered an “old” middle class milieu. A clear “new” middle class milieu is the upper middle class milieu 2 with its growth focus. The middle class milieu 4, although only average in terms of socioeconomic status, may also be considered part of the “new” middle class: its relatively central position on the conservation vs. openness axis is due to high modesty and low hedonism. Thus, in our typology, the “old” (milieu 5) and “new” (milieus 2 and 4) middle classes are smaller (about 4 and 17% respectively) than assumed by Reckwitz, but there is some potential for coalitions in lower parts of the socioeconomic structure: the “old” middle class may form a coalition with milieus 8, and the “new” middle class may form a coalition with milieu 6. Moreover, we also find milieus that do not fit into Reckwitz’ class divides, e.g., milieu 3 as an upper middle-class milieu with a personal focus.

6 Conclusions

The aim of this article was to establish “social milieus” in the international debate as a conceptual and empirical tool for scrutinizing recent threats to social integration induced by socioeconomic inequalities and cultural conflicts in welfare societies. We recapitulate the German debate on social milieus—which was recently extended to the analysis of intergroup conflicts—and connect it to the international literature on sociocultural cleavages. Both the milieu and cleavage approaches highlight the need to supplement socioeconomic stratification with a cultural dimension of conflicting values. We refer to the most comprehensive approach to values, the basic human value approach by Schwartz, as a proper conceptualization of the cultural dimension.

Synthesizing these approaches, we define social milieus as large latent groups with similar socioeconomic positions and cultural values. Members of a social milieu share life chances because of their socioeconomic position. Additionally, they pursue similar values that are compatible within milieus and potentially conflicting between milieus. Correspondingly, we assume that social milieus exhibit distinct modes of within-milieu social integration that are potentially conflicting between milieus.

We empirically estimated a typology of nine social milieus for Germany using LCA, with education and income (socioeconomic dimension) and basic human values (cultural dimension) as indicators. In contrast to the most well-known milieu typology in Germany, the Sinus® milieus, this new typology is readily replicable, with publicly accessible survey data, includes the socioeconomic milieu dimension, and considers values more comprehensively. In particular, the consideration of self-enhancement and self-transcendence in addition to conservation and openness is a strong advantage over the Sinus® milieus.

In line with theoretical expectations, several milieus within similar socioeconomic strata were identified that differ in their value profiles. The resulting landscape of social milieus reveals that some of the ideal-typical group-specific profiles of socioeconomic positions and values that are present in the literature on sociocultural and political cleavages may in fact cover much smaller parts of the population than assumed. This finding applies in particular to Reckwitz’ (2019) distinction of an “old” and a “new” middle class that both encompass a third of the population. It is notable that an ideal-typical old middle class with a protection focus cannot be found in our typology. Possibly, such a milieu is either too small to be detected by our typology (and thus much smaller than assumed), or misperceived to combine self-enhancement and conservation while actually, there are separate milieus, some endorsing self-enhancement and others conservation values (combined with self-transcendence). By properly considering the socioeconomic positions of social milieus and their complete value profiles, the presented milieu typology may uncover conflicts and cleavages that have been overlooked previously. For example, we identified a rather large lower middle class milieu (milieu 8) with a self-enhancement focus that differs from the old middle class but may well come into conflict with the new middle class milieus.Footnote 10

From the range of limitations and future research avenues we highlight the following: first, the relationship between Schwartz’ values and other relevant concepts for analyzing both collective cultural conflicts between milieus and social cohesion within milieus, such as lifestyles, conduct of life, or cultural practices, call for further research. Second, the statistical model presented here calls for further robustness and sensitivity checks. Once consolidated, milieu models will have to prove their usefulness in competition with alternative concepts, such as occupational class schemes or lifestyle typologies. Third, more detailed pictures of the milieu landscape in Germany would need to consider regional, ethnic, and other group heterogeneity (e.g., West and East Germany, ethnic milieus, age, gender) (see Jünger and Schaeffer, this issue). Fourth, the mechanisms and historical processes of how social milieus emerge and unfold, their regularities and variations across countries and time, call for comparative research and theoretical foundations. Fifth, and finally, the relationships between social milieus, which have been highlighted only theoretically and preliminarily, require more in-depth analysis. How strongly are particular social milieus segregated or even isolated against each other, in terms of cross-milieu interactions or mobility? How does this affect the capabilities for mutual understanding and political compromise or coalitions between milieus? Although social milieus need to be clearly distinguished from political camps, they are nevertheless formative for political coalitions. Here, political mobilization and organizations play a crucial role, opening further avenues for historical and cross-national comparative research. Overall, a lot of research lies ahead. Our contribution here was to bring social milieus back on the agenda and stimulate discussion about studying social integration within and between social milieus.