JUBA, South Sudan — Pope Francis had waited years to visit one of the world's most troubled countries, with one planned trip scuttled because of the coronavirus pandemic, another because of knee pain. And when he finally touched down on Friday - to a marching band, to ululating crowds, to a city where stretches of road had been paved just for him - Francis said South Sudan had a "special place" in his heart.

But it is also a country in shambles.

A convergence of conflict, poverty and climate change have combined to create an astonishing set of traumas and obstacles - unresolved despite years of international mediation and personal attention from the pontiff, who in 2019 hosted rival South Sudanese leaders at the Vatican, kissing their feet and pleading for a "new age of peace and prosperity."

For a pope who has prioritized outreach to the developing world, majority-Catholic South Sudan presents the ultimate test of the church's ability to help in nation-building. With his 48-hour visit, Francis is trying to harness his personal power, to highlight the plight of a country that is rarely visited by foreign leaders and is sometimes dismissed as a lost cause.

Francis's most immediate goal on Friday was to suggest otherwise - urging the South Sudanese people to imagine a country without permanent conflict, pushing its leaders in particular to run the country responsibly, and end bloodshed and mutual recriminations. "Basta!" he said repeatedly in Italian, speaking to dignitaries and South Sudanese officials. Enough!

"No more destruction," Francis said. "It is time to build."

"History itself will remember you if you work for the benefit of this people that you have been called to serve," he said. "Future generations will either venerate your names or cancel their memory, based on what you now do."

South Sudan has oil and fertile land, but it is widely regarded as one of the world's most corrupt countries, with officials accused of using oil revenue for personal gain. The United Nations says key humanitarian indicators are at their "worst point" since independence in 2011. Three-quarters of the country depends on the World Food Program for food. Last month, six journalists were arrested after a video appeared that seemed to show President Salva Kiir urinating on himself during a public event.

That turmoil adds to the stakes for Francis, who is visiting in tandem with leaders of two other Christian denominations: the Anglican Archbishop of Canterbury, Justin Welby, and the Presbyterian Rt. Rev. Iain Greenshields, who is the moderator of the Church of Scotland.

A "pilgrimage of peace," they are calling it.

Speaking Friday evening, seated next to the other Christian leaders and Kiir, Francis said he had taken the trip after "hearing the plea of an entire people that, with great dignity, weeps for the violence it endures, its persistent lack of security, its poverty and the natural disasters that it has experienced." He said that years of war and conflict "seem never to end."

He specifically called for a "battle against corruption," saying that society risked being polluted by "the inequitable distribution of funds, secret schemes to get rich, patronage deals, lack of transparency."

While he has been criticized over the past year for going easy on Russian President Vladimir Putin, this time there was an edge to his diplomacy.

"I realize that some of what I have had to say may appear blunt and direct, but please, know that this arises only from the affection and concern," the pope said.

In an interview, the mayor of Juba, Michael Allah-Jabu, said the pope's trip, above all, would give South Sudanese people the "feeling of love."

"This can be a historical event in the history of the country," he said. "I do think with time - with time - people can change."

For Francis, South Sudan marks the second leg of a challenging - but so far enthusiastic - trip to Africa, which started in the Democratic Republic of Congo. In Kinshasa, ecstatic crowds filled stadiums and airport fields, or staked out spots along the road just to catch a glimpse. But in a sense that part of the trip was easier; while the Congo also has profound and pervasive problems, the epicenter of its violence is in the east, some 900 miles away from the capital, to which Francis restricted his visit.

In South Sudan, the trauma is in closer proximity, with the upheaval wholesale. Either because of conflict or recent flooding, roughly 1 in every 3 South Sudanese people has been forced to flee their homes.

That outcome is especially deflating given the jubilation - and brief period of hope - when South Sudan a decade ago conducted a referendum to break away from majority-Muslim Sudan. Led by Kiir, with his trademark 10-gallon cowboy hat, South Sudan became Africa's 54th state, cheered by the West.

From the outset, South Sudan had some of the lowest benchmarks for living standards in the world. But the situation soon got worse. The two most relevant political figures - Kiir and his deputy Riek Machar - turned against one another, a power struggle that triggered full-on warfare between the two largest ethnic groups, the Dinka and the Nuer.

The civil war is now over, and Kiir and Machar - who together met with the pope in 2019 - have made a tenuous peace, presiding in a unified government. But crucial elements of the peace deal remain unfulfilled, most importantly the formation of a unified army merging forces loyal to Machar and Kiir.

Kiir said Friday that, "in honor of the pope's visit," his government would reenter talks with those parties, after previously saying the negotiations were being used by opponents as a stalling tactic to prepare for war.

Generations scarred by ferocious war continue to fight in a constellation of small, complex conflicts - fueled by the guns with which the country is awash. Some smaller parties have not signed the peace deal.

"The situation is horrendous in South Sudan, and it seems to keep getting worse despite the peace deal," said Alan Boswell, the Horn of Africa project director for the International Crisis Group think tank. The deal created a truce among the elites, he said, "but a lot of the rest of the county has descended into various forms of conflict and insecurity, with huge death tolls that would be shocking anywhere that wasn't South Sudan."

Climate change is also contributing to conflict, as cattle herders, in the wake of flooding, have sought out drier land, sparking battles over territory.

The capital itself has stabilized, and people familiar with Juba say it has developed quickly, if unevenly, in the past few years. It now has a few luxury hotels and more paved roads. But the situation deteriorates not far beyond the city limits. Even as the pope was arriving, South Sudanese media reported that 20 people had been killed 70 miles from Juba, in what one outlet described as a "cattle-related attack."

Houreld reported from Nairobi.