Billy Graham speaks on stage on the last day of his farewell American revival in New York on June 26, 2005. (Henny Ray Abrams/AP)

This post was first published in 2015. It was updated Wednesday. 

The death of charismatic evangelist Billy Graham on Wednesday put an end to his six-decades-long presence as “America's pastor” that reverberated far beyond U.S. borders. Apart from reaching millions through books and columns in newspapers, Graham also inspired a movement that is only now becoming truly global: mass rallies at megachurches.

Often located in stadium-like venues, these churches can grow to attract tens of thousands of people. And while the United States under influential figures like Graham may have started the trend, the future of megachurches probably lies abroad. 

Graham never established his own megachurch, but his style and global reach still served as a role model to many of those who sought to attract similarly big communities across the United States and elsewhere.

Despite American roots that reach back to the 19th century, megachurches abroad now have a higher average attendance, even though the vast majority of megachurches are still in the United States. While there are 230 to 500 such churches elsewhere in the world, the Hartford Institute estimates that there are about three times as many American megachurches.

Based on data from the Hartford Institute for Religion Research and from the Christian nonprofit organization Leadership Network, The Washington Post visualized this global and diverse movement. We used the most common definition of megachurches, which describes them as having “2,000 or more persons in attendance at weekly worship, a charismatic, authoritative senior minister, a 7 day a week community,” and other features, which you can find in detail here.

In the United States, the median weekly attendance is about 2,750, while the median weekly attendance at world megachurches is nearly 6,000. One factor that could explain the larger sizes on other continents is a lack of alternatives for believers.

Challenges have slowed international expansion

“Outside the United States, it takes a large amount of charisma and capital to create a megachurch,” said Scott Thumma, director of the Hartford Institute, in an interview conducted in 2015. In the United States, however, competition among megachurches is fierce because it is easier to establish such communities. “It is harder to be massive here in U.S.," Thumma added, citing zoning laws, safety inspections, construction and property costs.

Nevertheless, he believes that smaller megachurches do not lag behind in international comparison. “I was just at four megachurches within a few miles of each other in Atlanta, and each of these cater to a slightly different audience,” Thumma said.

The differences between U.S. and global megachurches can even be noticed on satellite images. Abroad, megachurches are often constructed in the centers of cities, where they are accessed by foot, subway, bus or cab. In the United States, community members usually access the churches by car. To provide the necessary parking lots, U.S. megachurches are often in suburban areas.

Non-U. S. worship buildings are constructed vertically because of limited urban plots of land, whereas larger American churches are spread out horizontally.

According to Thumma and his research colleagues, the different locations are also reflected in the members' profiles: Whereas the average U.S. megachurch member has a middle or upper class background, this is less true abroad.

With the exception of Chicago, the cities with most megachurches in the United States are in the south or west. Texas stands out in particular with four cities (San Antonio, Dallas, Houston, Austin) having more than 11 megachurches respectively. Houston and Dallas are also in the top 10 of the world's cities with the most megachurch attendants.

Compared with smaller religious communities, U.S. megachurches offer a variety of services such as financial counseling or education, day care, preschool or after-school programs and initiatives focused on employment and job placement.

Despite differences between U.S. and global megachurches, the idea of providing services to members has been widely copied.

Why foreign megachurches will define the movement's future

Attendance is high in western and eastern Africa: At least 25 of the region's churches are in Nigeria. The country's population is set to reach about 900 million by 2100, probably contributing to a further growth in Protestant believers. In demographically shrinking Europe, Protestant megachurches already seem to be fairly absent from the south of the continent where Catholicism is predominant. The sizes of northern European megachurches lag far behind when compared with those in Africa, Asia and South America

One mostly blank spot on the map is China, the world's most populous country. A survey of 65 countries, conducted by Gallup International and the WI Network of Market Research, showed that China was one of the world's least religious nations, by far.

Although reasons for the surge in global megachurches differ, urbanization and economic growth have played a significant role in countries such as South Korea. “The megachurch model helped acclimate thousands of displaced rural migrants into a community and urban reality following the Korean War and rapid modernization,” said Thumma, who has spent about 25 years researching the topic.

Will the movement last?

“The spread of the megachurch model will continue in the developing regions of the globe,” Thumma explained. “I expect the most rapid growth to be in Asian countries as they continue to develop and populations concentrate in massive urban areas from rural communities.” Such developments could be especially groundbreaking in China, which has so far restricted the growth of religious assemblies or communities.

Lazaro Gamio contributed to this report.

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