Modern academic sociology began with the analysis of religion in Émile Durkheim's 1897 study of suicide rates among Catholic and Protestant populations, a foundational work of social research which served to distinguish sociology from other disciplines, such as psychology. The works of Karl Marx and Max Weber emphasized the relationship between religion and the economic or social structure of society. Contemporary debates have centered on issues such as secularization, civil religion, and the cohesiveness of religion in the context of globalization and multiculturalism. The contemporary sociology of religion may also encompass the sociology of irreligion (for instance, in the analysis of secular humanist belief systems).
Sociology of religion is distinguished from the philosophy of religion in that it does not set out to assess the validity of religious beliefs. The process of comparing multiple conflicting dogmas may require what Peter L. Berger has described as inherent "methodological atheism". Whereas the sociology of religion broadly differs from theology in assuming indifference to the supernatural, theorists tend to acknowledge socio-cultural reification of religious practice.
Classical, seminal sociological theorists of the late 19th and early 20th century such as Émile Durkheim, Max Weber, and Karl Marx were greatly interested in religion and its effects on society. Like those of Plato and Aristotle from ancient Greece, and Enlightenment philosophers from the 17th through 19th centuries, the ideas posited by these sociologists continue to be examined today. More recent prominent sociologists of religion include Peter L. Berger, Robert Neelly Bellah, Thomas Luckmann, Rodney Stark, William Sims Bainbridge, Robert Wuthnow, Christian Smith, and Bryan R. Wilson.
Durkheim, Marx, and Weber had very complex and developed theories about the nature and effects of religion. Of these, Durkheim and Weber are often more difficult to understand, especially in light of the lack of context and examples in their primary texts. Religion was considered to be an extremely important social variable in the work of all three.
"Marx was the product of the Enlightenment, embracing its call to replace faith by reason and religion by science." Despite his later influence, Karl Marx did not view his work as an ethical or ideological response to nineteenth-century capitalism (as most later commentators have). His efforts were, in his mind, based solely on what can be called applied science. Marx saw himself as doing morally neutral sociology and economic theory for the sake of human development. As Christiano states, "Marx did not believe in science for science's sake…he believed that he was also advancing a theory that would…be a useful tool… effecting a revolutionary upheaval of the capitalist system in favor of socialism." (124) As such, the crux of his arguments was that humans are best guided by reason. Religion, Marx held, was a significant hindrance to reason, inherently masking the truth and misguiding followers. As we will later see, Marx viewed alienation as the heart of social inequality. The antithesis to this alienation is freedom. Thus, to propagate freedom means to present individuals with the truth and give them a choice to accept or deny it. In this, "Marx never suggested that religion ought to be prohibited." (Christiano 126)