By Bruce Kennedy
CNN Interactive

It will be hard for future historians, when they consider the 20th century, to view much of the era in a positive light. The past 100 years have taken mankind to new lows, with unprecedented levels of violence, barbarity and cynicism.

But along with this darkness, and perhaps in part because of it, has come a new international resurgence in religion, faith and spirituality at the century's end.

Consider some of the statistics found in recent polls and surveys:

• The number of evangelical Christians in the world has grown by 126 percent since 1970.

• According to a Pew Research Center survey released in December 1997, 71 percent of Americans said they "never doubt the existence of God," up 11 percent from a similar survey a decade earlier.

• About one out of every five people in the world today is Muslim, compared to one out of seven in 1950.

• There are more than 10 million Mormons in the world today, up from about 4.6 million in 1980.

While some of the numbers may reflect religion-switching, experts say the overwhelming trend indicates a growing faith among humans.

Religion is also making inroads in popular culture. One of the more notable examples is the widespread appearance of angels in recent years on everything from calendars to bookmarks to TV commercials. "Touched by an Angel" has been one of the top-rated U.S. television programs in the 1990s. Angel-related motion pictures such as "The Preacher's Wife" and "Michael" were box-office hits during the winter of 1996-97.

These facts and figures are all the more surprising considering the number of premature obituaries written for religion and spirituality during the 1960s.

"I think a lot of that 'God is dead' thought came out of very shallow anthropology, what it means to be human," says Joseph Kelley, adjunct professor of religious studies at Merrimack College in Massachusetts. "If you look at Marxism, the conviction that one can build a perfect society, it seems so naive. A lot of that naiveté about what motivates us, what type of interior life we have, goes back to the 19th century."

Kelley cites the example of his students, who are "surrounded by a world that can seem real shaky at times. I see them looking for some thread of meaning, purpose. What I see myself doing in theology is just giving them a vocabulary, a style ... something you can use to think about your experience."

In the United States, that religious experience is also mirroring current attitudes about lifestyle and competition in the marketplace -- as many decide to take what they like from different faiths and "design" their own spirituality.

"This 'pick and choose' approach to faith, the desire to 'take from it what is wonderful and good,' will continue in the coming century," say Richard Cimino and Don Lattin, authors of "Shopping For Faith: American Religion in the New Millennium."

"The same consumeristic and experiential approach popularized via Eastern mysticism will be brought to the traditional spiritual teachings of the West," the authors predict.

"About two-thirds of the country is affiliated with a church," notes Phillip Lucas, associate professor of religious studies at Stetson University in Florida, "and about 60 to 70 million are not. A lot of [the unaffiliated] began spiritual odysseys during the 1960s, when they lost confidence in mainstream religious institutions. ... At the same time, many people have simply decided that institutional religion is not for them. ... People are not identifying with the religions of their birth as they did before."

Lucas says the Pentecostal and charismatic churches are growing rapidly because of their focus "on the personal experience of the divine. When people come out of a Pentecostal service, they've experienced something."

He also points toward a 30-year cycle of religious resurgence in America as a factor in the current interest in faith and spirituality. There is also the uncertainty many feel as the century ends and the new millennium begins.

"As public life becomes more immoral, fragmented and self-centered, there's a desire to find something beyond the seeming social Darwinism of American society," Lucas says.

The approach of the new millennium also has brought with it a dangerous religious angle, as apocalyptic and end-of-time groups emerge. In 1997, 39 members of the Heaven's Gate cult killed themselves in a San Diego mansion -- after being assured by their leader that they would link up with a spaceship hiding behind the Hale-Bopp comet.

What the next century holds for religion is a subject of wide debate. Observers predict that Catholicism may undergo massive changes -- especially with the passing of the current pope. The authors of "Shopping for Faith" note that a recent publication of the "Catechism of the Roman Catholic Church" was a surprise best-seller -- and they speculate that the book's sales "point to a desire for American Catholics to measure their own views of their faith against a more ancient and universal standard."