On Sunday , the people of south Sudan will begin the process to decide whether to split Africa's largest country in two and form the world's newest nation, or to reunite with their neighbors in the north.

The seven-day referendum was part of the January 2005 Comprehensive Peace Agreement that ended 22 years of civil war and gave the south autonomy leading up to the election.

Monitoring the referendum closely, from 7,000 miles away, will be members of the Episcopal Diocese of Missouri, who have had a "companion relationship" with the Episcopal Diocese of Lui in southern Sudan since 2006. Some Episcopal congregations in the diocese also have individual relationships with congregations in the Lui diocese.

"The main point, theologically, is the relationship itself," said Debra Smith, the Missouri diocese's representative of the American Friends of the Episcopal Church of Sudan and wife of Missouri Bishop George Wayne Smith.

"The church is the body of Christ and each church is part of that body. To get to know someone from a different culture who shares the same beliefs and liturgical practices is mind-broadening and spiritually invigorating. "

Southern Sudan is one of the poorest, most isolated places on the planet. The civil war cost more than 2 million lives, and today millions more are dependent on food aid, according to the International Rescue Committee. Decades of war and violence have left the region's economic and social infrastructure in ruins.

The political reality of Sudan today is tied closely to its religious makeup. Muslims, mostly in the north, make up 70 percent of the country's religious population, compared with Christians, who make up about 5 percent of the population and live mostly in the south and in Khartoum, the capital.

In September, the presiding bishop of the Episcopal church, Bishop Katharine Jefferts Schori, called for "A Season of Prayer for Sudan" in preparation for Sunday's referendum.

In response, the Missouri diocese will hold a prayer service tonight at Christ Church Cathedral from 6 to 7 p.m.

At 10:15 a.m. on Sunday, the cathedral will host an educational presentation about the diocese's relationship with the Lui diocese (there's also more online at luinetwork.ning.com). Art created by children from Lui will be on display in the nave of the cathedral all weekend.

When the first group from the Missouri diocese made a trip to Lui in 2003, before a formal relationship was ironed out, its members consulted with an Episcopal priest familiar with Sudan's politics, former Sen. John Danforth.

Danforth, a former U.S. special envoy to Sudan, was one of the architects of the 2005 Comprehensive Peace Agreement. Since then, Danforth has kept tabs on the progress in Sudan. He said the country "geographically straddles the fault line between Arab Africa and black Africa."

"Arab Africa has been the dominant political force in the country, and non-Arabs have felt they've been oppressed," Danforth said.

The New York Times reported this week that, in a visit to the south Tuesday, President Omar al-Bashir offered "a conciliatory message," saying he would be 'sad" if Sudanese in the south voted to secede. The International Criminal Court has charged al-Bashir with war crimes and genocide for unleashing the Arab militia known as the janjaweed in the country's Darfur region.

"But at the same time, I will be happy if we have peace in Sudan between the two sides," he continued. "We cannot deny the desire and the choice of the people of the south. This is their right."

Danforth called al-Bashir's comments "very good news."

Those on the ground say a vote for secession is all but ensured. If that happens, southern Sudan will become its own country on July 9, exactly six years since the peace agreement.

The Rev. Emily Bloemker, associate rector at St. Timothy's Episcopal Church in Creve Coeur, is chairwoman of the Missouri diocese's Lui committee. She returned from her third visit to Lui in November.

She said priests were preaching separation while she was there, with one comparing the oppression of the south by Khartoum to the enslavement of the Hebrew people by Pharoah.

"But privately, people are expressing a great deal of fear," Bloemker said. "War was not so long ago, and they know what's coming if war takes place. They do not trust the northern government will not respond with force."

According to the International Monetary Fund, oil accounted for 93 percent of Sudan's exports and 50 percent of domestic revenue in 2009. About 98 percent of southern Sudan's budget comes from oil revenue, according to the U.S. Energy Information Administration.

The European Coalition on Oil in Sudan, based in the Netherlands, says about 80 percent of Sudan's oil output is pumped in the south — which is landlocked. The north controls the only means, by pipeline, of getting the oil out.

"There's no possibility of the country staying together," Danforth said. "That's not the real question. The question is whether there can be a détente between what will now be two countries, so they can agree on a way of both developing oil resources, and transporting it out of country."

The real danger, he said, is that the government in the north may not recognize the results of the referendum, and could therefore return to violence in the south as a way of controlling the independence movement and flow of oil.

That danger leads to the very real fear that Missouri Episcopalians have for the people of Lui who are no longer just a faceless group of Africans 7,000 miles away, but friends. Adding to the tension in the Lui diocese is that they were left leaderless when their bishop, Bullen Dolli, died in December.

"We fear our friends are going to be murdered if there's violence," Bloemker said. "When we hear about potential violence, I think about Mama Margaret who survived the first civil war. But now I know her, and the idea of her not surviving more violence is heartbreaking. For us, this vote is about individual lives and relationships as opposed to a geopolitical game."

Those personal connections make the prayer service at Christ Church Cathedral on Saturday night much more fraught. It makes the prayers for peace that much more urgent.

"I have to think that's what Jesus wants from us," Bloemker said. "To not allow violence to become a personless force. In that sense, the relationship we have with Lui is very effective in transforming our lives in Missouri."