Americans tend to think of their society as deeply respectful of individual preferences and choices and apply this belief especially to people's rights to choose their partners. However, statistical studies have indicated that many social forces narrowly contain marriages within the basic strata that mark American society. To some extent, this pattern follows personal considerations of compatible identities, interests, and experiences that husband and wife may share. However, it is also subject to social pressures of family, peers, and the wider society, which often looks askance at unions of couples from disparate backgrounds. It may even impose penalties, extending to the point of ostracism.
Although American society is easily categorized as a class society, the actual patterns of stratification are difficult to categorize, especiall since they are complexly interrelated to ethnic, racial, and religious considerations. Many studies have shown that Americans tend to marry within general social class boundaries. The pattern is particularly apparent if educational background, a major component of class definition, is considered. A analysis of marriage patterns current in 1988 (Blackwell 1998) revealed a strong tendency for people to seek partners with similar educational attainments, especially at the extreme ends of the hierarchy. Men with a six years of schooling or less were more than ten times as likely to marry wives with an equivalent educational attainment than were men with higher education levels (39% as opposed to 3% of the stratum) Only about 20% of this group married women who had finished high school, and less than 1% married college graduates. At the other end of scale, approximately half the men who had received a university degree were married to other graduates and an additional 30% had wives who had received some postsecondary training. Less than 2% were partnered with women who had less than 12 years of formal education, a proportion exactly equal to the national rate of interracial marriages. (See a discussion of American caste endogamy.) Thus education stands as a major social division that determines and patterns conjugal and in-law relations. More importantly, while racial endogamy rates have generally declined, those for educational status are noticeably increasing. This trend in marriage patterns points to a broader reorganization and polarization of North American society according to education levels.
Religion constitutes a second but related arena of marital choice in American society. In this case endogamy is imposed by structural rules as well as predominant preferences. Many religions, particularly Catholicism, Judaism, and Islam, have specific regulations that both partners must subscribe to the appropriate faith in order to contract a recognized marriage within it. Some Protestant groups are more open but nevertheless stress the importance of a common religious bond for conjugal cooperation and child socialization. In general, rates of religous endogamy differ according to the specific tradition involved as well as a number of other circumstances. A 1982 Canadian study estimated a 78% endogamy rate for Jews, 56% for Catholics and 45% for Protestants. However, the latter group varied according to sect, from 62% for Menonites to 37% for Presbyterians (Ramu 1993:48). Religious endogamy was more pronounced in the larger cities, in which it was easier to find a partner from the same background. A study of American interfaith marriages among Christians in 1988 showed similar results (Lehrer 1998). The groups involved were classified into three categories: Catholics, "ecumenical" Protestants, and "exclusionist" Protestants. In all three cases the in-marriage rate was approximately 50%, although Catholics were slightly more likely to marry within their faith than either Protestant category. As in the Canadian study, locations with larger numbers of coreligionists demonstrated higher endogamy rates. More importantly, the study traced changes over time and found that the incidence of interfaith marriages almost doubled for Catholics and ecumenical Protestants between 1950 and 1988, but remained constant for exclusionist Protestants. Accordingly, the mainline religious groups are becoming more open and flexible on a personal if not official level. The more exclusionist Christian groups are retaining their inward looking traditions. This finding is particularly significant insofar as the fundamentalist and evangelical sects represented in this category have been showing rapid growth at the expense of the other denominations and are increasingly molding the North American religious landscape.