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Exploring Religion

Session 2: Overview

Religious Diversity

Learning objectives

  • An increased awareness of the global variations in religion.
  • An increased awareness of the religious variations in religion in the U.S.
  • Increased understanding of the organizational and historical diversity of religions.

This week you explore the rich diversity of religions across the globe. Videos from the previous module reviewed how the major world religions differ in their beliefs and practices. In this module we look at the rich diversity and sharp differences within world religions, giving close attention to the diversity of Christians in the United States. Did you know that there are more than 2,000 different religious groups in the U.S. alone? Or, that there are more than 300,000 local religious congregations, with many of them not affiliating with any of the 2,000-plus religious groups? Moreover, this diversity is not limited to America or one world religion. Every world religion has a multitude of divisions. This module will help you trace the lineage of a few of these groups and will allow you to sample the wide variation of religions that are populated across America and the globe.

So why does the United States have more than 2,000 different religious denominations?  The activity on “Exploring Denominations” introduces a few tools for retracing how religious groups arise, split and merge in the U.S.  Although not addressed in this activity, the denominational splits and mergers can occur for a variety of reasons.  As you might expect, differences in key beliefs or teachings are often a source of tension. However, ethnicity, race, worship styles, language, organizational structures, finances, region and a host of social markers can generate tensions leading to schisms.  Likewise, when these barriers are reduced, mergers are more likely.  Yet, this brief activity has a couple important limitations. First, the religion family trees on the ARDA present the lineage of hundreds of American denominations, but hundreds of smaller groups are omitted because there is so little information on them. Second, the largest denomination in the U.S., the Roman Catholic Church, is omitted as its lineage is a bit different than all of the other religious groups. Third, looking only at the U.S. and primarily at Christian groups might suggest that religious diversity is largely confined to Christianity in America. But this is certainly not the case. Because the U.S. has a history of religious freedom and immigration and a diversity of ethnic groups, there is a wide variety of religious groups in the U.S. that reflect much of the religious diversity of the world. We encourage you to also look at the global family trees for Islam, Buddhism and Judaism. Even these seemingly detailed trees represent only a small fraction of the different religious groups in the world.

FamilyTree Islam

The remaining readings and activities primarily focus on where religious groups are located and how they are changing in size and location over time.  Although religion often is perceived as being stable across regions, you will find some important changes when you look over time. Changes in the size and distribution of religious groups often reflects major social changes or the activities of religious movements. For example, as a result of the efforts of African Christians building on earlier Western missionary work in Africa, the indigenous religions in Middle Africa plummeted from 75 percent of the population in 1921 to six percent in 2015, as the percent Christian went from 18 to 80 percent. Shifts in the religious profile of a nation also can result from major political change. The percentage of non-religious in Eastern Europe rose to 40 percent during the time of the Soviet Union, but then fell sharply following the break up of the Soviet Union and is now below 10 percent. In contrast, the percentage “not religious” has risen sharply in Western Europe, from two percent in 1921 to 27 percent in 2015. 

Finally, we offer a few more videos explaining how different religious groups worship and what they believe. The interview with Dr. Gina Zurlo will give you the inside story on how the data on religious groups are collected. With so many religious groups across the globe, and with often different standards for claiming adherents, how do social scientists decide how many are in each group?  We will talk with one of the principal investigators collecting this data to learn more.

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