When Catholicism’s cardinals meet in the Sistine Chapel to select a new pope, they will be surrounded by an explosion of divine artistic images in one of the most famous places on Earth to seek the face of God.

And pretty much all they will see when they look on the walls and ceilings are white faces — of Jesus, Mary, God, Adam, Eve, angels, prophets. That will also largely be true when they lower their eyes and look at one another.

Although most experts agree the odds are long, it’s hard to imagine a more transformative choice the cardinals could make than to select a nonwhite person to lead the world’s largest faith denomination, 1.2 billion strong. In the conclave that begins Tuesday, that would mean a person from the developing world, which is now home to two-thirds of all Catholics.

After centuries and centuries of white European popes, a developing-world pope could further alter the modern concept of Christianity, and by extension the modern concept and geopolitical tilt of power.

In conversations, comparisons to Barack Obama’s election as the United States’ first black president readily arise. But there is ostensibly a major difference: American presidents are picked by voters driven by pragmatic concerns, while popes — in Catholicism, God’s representatives on earth — are picked by cardinals led by the Holy Spirit.

How long does it take to elect a pope?

The process, in other words, is supposed to be above earthly concerns such as race and ethnicity.

“That’s not how we do things,” bristled Mary L. Gautier, a sociologist and researcher with the church’s best-known U.S. data bank, the Center for Applied Research in the Apostolate, when asked for historical demographics on race and ethnicity within the church. There is no central repository for the data, Gautier said, and race is a social construct, anyway.

“The church has always been and considered itself a global church,” bound by its common humanity, she said.

But the reality is that the majority of the 115 cardinals are white men from Europe, where the Catholic population is decreasing, at the same time it is growing rapidly among people of color in the developing world.

Between 1910 and 2010, the percentage of Europeans who identify as Catholic decreased from 65 percent of the global Catholic population to 24 percent, according to an analysis by the Pew Research Center of data from the World Christian Database. Latin Americans climbed from 24 percent to 39 percent, and Catholics in sub-Saharan Africa went from less than 1 percent to 16 percent. Catholics from the Asia-Pacific region went from 5 percent to 12 percent of the world Catholic population, according to the Pew Research Center.

‘Equal in God’s eyes’

The church’s demographics are undergoing a major shift in the United States, as well. Among Catholics over the age of 65, just 16% are Hispanic, while among Catholic adults under 40 that figure is 47 percent.

The election of a pope from Latin America or Africa, in particular, is seen by some as a way to send a powerful message that the church perceives a need to change.

“We need to renew what is going on,” said the Rev. Jose Hoyos, a Colombian who runs Spanish outreach for the Arlington Diocese. “If we had a Latin American or African pope, it would be a good way of telling us that the church is not prejudiced, that we are equal in God’s eyes. It’s not about the color of your skin, but it’s about healing the many wounds in our lives of prejudice. It’s about getting closer to Jesus Christ.”

The cardinals from the developing world whose names have been mentioned as potential popes include Malcolm Ranjith of Sri Lanka, Luis Antonio Tagle of the Philippines and Peter Turkson of Ghana. Even within the group of contenders, there are complicated questions of race and ethnicity. The term Hispanic refers to ethnicity, and members can be of any race, including black, indigenous, white or mixed race. For example, is Cardinal Odilo Scherer of Brazil a developing-world pope, even though his family came from Germany?

Also, in Brazil as in much of Latin America, people have not historically classified themselves neatly into racial categories.

“The question Latin Americans would press would not be about race but about a non-European,” said Jose Casanova, a prominent sociologist of religion at Georgetown University, who is from Spain.

He acknowledged the sometimes tricky effort to separate these topics. “Officially, Christianity is not about these matters [such as race],” Casanova said. “But in the world those inequalities still play a role. So it is important that whoever represents the Christian message comes from the groups who are less privileged.”

But such parsing may be largely irrelevant because of a perception that developing world cardinals lack the experience for the papacy, according to many Vatican watchers.

Even though Christianity has existed throughout the world, institutional Catholicism is relatively new in places such as Africa or Asia. Until World War I, in fact, most non-European branches of the Catholic Church were considered “missionary” churches; it took the Second Vatican Council of the 1960s to encourage the idea of indigenous clergy. While the clergy has diversified slightly since then — in part because European and American men are not becoming priests as quickly — Europe still has more priests than Africa, South America and Central American combined. In the United States, only 15 percent of U.S. priests ordained last year were Hispanic, while 71 percent were white.

The real stumbling block of developing-world cardinals “is they don’t have Vatican experience at a time when they need someone who can get control of the management issues in Vatican City,” said veteran Vatican reporter John L. Allen Jr. with the National Catholic Reporter.

Allen conceded that a pope of color might trigger “a bit of a shock to the system.”

“But it was a shock when they picked someone from Poland in 1978, and from a Catholic point of view, that turned out pretty well,” he said. “I don’t think this is on the minds of the cardinals.”

The “not enough experience” argument sounds like racist code to some. Pope John Paul II, for example, had no experience in the curia, or Vatican bureaucracy. And in pockets around the world, there remains a sense of incredulousness at the notion of a pope of color.

“It’s unlikely the next pope will be someone from Africa or South America. You see, the papacy is sophisticated,” said Bernard Barringer, a 73-year-old retiree and devout Catholic emerging from a Latin Mass held last week in the upscale Kensington neighborhood of London.

“But of course,” he added, “nationality and color are irrelevant. It’s the man who matters.”

‘In wealth and power’

Based on their perceptions of the Obama presidency, some black Catholics were wary of how a pope of color might be greeted on the world stage.

“Having a black president hasn’t solved the race problem, it’s only exacerbated things, the language, the way we talk to one another,” said Rev. George Quickley, 66, who pastors a black and Latino congregation in Oakland, Calif. “I think a [pope] from Africa, all those negative perceptions about Africans, it would be used just as much to discredit a pope as it has been to discredit Obama.”

Race and ethnic background are but one consideration; politics and worship traditions are another. Some wondered about a pope coming from a very conservative culture in Africa or India, for example, where conversations about sexuality or the role of women sound different from those in the West.

Turkson shocked some when he said Africa wouldn’t likely have the clergy sex abuse issues that have exploded in the West because homosexuality “is not countenanced in our society.”

The Rev. Gregory Chisholm, pastor of the largest black parish in Harlem, felt pulled in two directions by the concept of an African pope. On the one hand, he “wouldn’t be encouraged on the rather traditional roles men and woman play in those cultures, “he said. “We’re just getting to the point where these European cardinals are at least opening their eyes that women can be as effective managers and leaders of our faith as men can be. And you wouldn’t want anyone to roll that back. . . . That would be disastrous.”

But he started to chuckle as he conjured an image of an African pope dancing and drumming at a St. Peter’s service.

“Africans have learned to really celebrate liturgy, and that would be an encouraging influence. That would be a bright possibility,” Chisholm said.

While the cardinals may be surrounded during the conclave by European imagery, many believers around the world are exposed to images that more closely mirror their congregations.

For example, the most popular Catholic shrine in the world, the Virgin of Guadalupe, venerates a Mexican image of the Virgin. The Basilica of the National Shrine, in Northeast Washington, the largest Catholic Church in North America, has used donations from ethnic communities to create diverse images of Jesus and and Mary as Lebanese, Polish, Indian and Cuban, to name a few.

The blond Jesus comes from a time “when Christianity was dominated by Europe in wealth and power,” said Nora M. Heimann, chair of the Catholic University art department. “I think that iconography lingers in the popular imagination, but does that mean Catholics aren’t open?

“In general terms, yes. But in specific terms, how would we have answered those questions before Obama was elected? We didn’t know until we saw it.”

Anthony Faiola and Eliza Mackintosh contributed to this report from London, and Scott Clement and James Arkin from Washington.