An hour before dawn breaks, rhythmic drumbeats and songs ring through the hulking barge that is returning hundreds of Bor Dinka to their war-ravaged homeland 15 years after their departure. Moored on the River Nile, they are within hours of reaching home. 

"I feel like the happiest man alive," said 60-year-old Michael Garang, a wide grin on his face. "I did not feel well in exile. Today I am returning to my land." 

On the shore, there are others returning too. The men herd the group's 300,000 head of cattle north, back to Bor, the dusty southern town that was the scene of the army mutiny in 1983 that marked the resumption of the civil war. 

A smell hangs in the air, the musty smoke of dung, burnt to keep the insects away. When moments later the conical grass huts and the tethered cattle come into view, the women dressed in their bright, striped shawls press out onto the barge's galleries and shout their greetings.

The International Organisation for Migration (IOM) is leading a multi-agency initiative to assist around 12,000 Bor Dinka in returning home from the vicinity of the southern capital, Juba. The elderly, the women and the children are being transported down the Nile by barge, allowing the men to move faster with the cattle, and reach Bor before the rains come in May. 

The return of the Bor Dinka is part of a wider trend. Hundreds of thousands of southern Sudan's four million displaced have returned since the Sudan People's Liberation Movement/Army (SPLM/A) signed the Comprehensive Peace Agreement with Khartoum's Arab-dominated government in January 2005, ending Africa's longest-running conflict. The United Nations expects a further three-quarters of a million to return before the end of 2006. 

During a visit to the region in early April, Jan Egeland, the UN's Under-Secretary-General for Humanitarian Affairs, warned that after the "marathon" of Operation Lifeline Sudan - an emergency effort - the international community should not "falter at the last hurdle".

"With nearly two million dead, this has been, together with the war in the [Democratic Republic of] Congo, the worst conflict of our generation," he said, adding that it was important to cement the peace, which involved the successful reintegration of returnees. 

They have come from Khartoum, from across the south, from Uganda, Kenya and the Democratic Republic of Congo. Some have returned to the vast open tracts of countryside; others to the south's dusty and growing towns. The return of so many people, with their different experiences of exile and expectations of return, poses an enormous challenge for the nascent government and the international aid agencies.

Surveying the Nile's flatlands from the roof of the barge's bridge, IOM's Jean-Philippe Chauzy said the Bor Dinka's "chances of integration are very good because they have their wealth with them - their cattle. Other groups have lost their cattle and so their prospects are far worse." 

Cattle have a central role to play in rural Sudan. Like a great walking pouch of gold, they provide self-sufficiency but also frequently entice jealous rustlers and thieves. 

Pastoralists such as the Dinka make few friends by herding thousands of cattle across other people's farmland, destroying crops and livelihoods in their wake. Hundreds have been killed and tens of thousands displaced in the last year in Yambio and Mundri during fighting between Bor Dinka and indigenous farming communities, making negotiation and conflict resolution a priority.

Enormous needs

Successful urban reintegration is reliant on rapidly extending services and infrastructure. Schools, hospitals, roads and jobs are needed, and needed fast, but there is barely the semblance of a working government.

The task is massive. Just one percent of women and girls have completed primary school, while Juba has only one paved road. 

"How can you bring your child back here if there is no school, no health facility and no road," asked James Anyang, 35, who returned from Kenya to work for a United Nations agency in Bor.

Others have come back but say the lack of progress could make them reconsider their decision. "It just didn't feel like home," 31-year-old Ayuen Samuel remembers thinking after returning to Bor in February from a refugee camp in northern Uganda. "I felt like going back the same night."

"When I tried to go to the so-called hospital it wasn't even up to being a primary health centre. You felt the building would fall down any minute and the nurse was without any qualifications," he added.

"Things that governments do everywhere in the world just don't happen here," said David Gressly, UN deputy resident and humanitarian coordinator for southern Sudan. "There isn't even a working banking system. Institutions need to be built from scratch."

The UN Children's Fund has promised to fund 1,500 new schools to address the government's number one priority - education. "[About] 3.8 million books are going out as we speak to every known class room in southern Sudan," said Gressly, "even if that class room is the shade under a tree."

Rich in oil and gold, a peaceful south bears the promise of an injection of billions of dollars. The valuable natural resources are a blessing provided they can be harnessed to deliver real development to a population setting about rebuilding their lives.

Institutional capacity will be crucial to marshal those resources, Gressly added. "If the government isn't rapidly built up then the resources cannot be translated into anything on the ground. Peace itself could be at risk."

Hopes of a new dawn, fuelled by a wealth of oil and gold, are tempered by fears that outbreaks of banditry and militia fighting could spark renewed conflict if frustration at the slow pace of change continues to fester.

It wouldn't be the first time. The recent civil war may have started in 1983 but southern Sudan has been at war for nearly forty of the last fifty years. When SPLM/A leader and newly appointed Sudanese Vice-president John Garang died in a helicopter crash in July 2005, many feared a return to violence, but for now the desire for peace has prevailed.

Insecurity and cholera both led to delays in the resettlement of the Bor Dinka. "The moment safety or dignity are compromised we stop the operation," said Terence Pike, who works for the UN refugee agency and is charged with the protection of those returning on the barges. 

Insecurity prevents agencies from working freely, particularly in the southern region of Equatoria, where UN compounds in Yei and Yambio have been subject to attacks from drunken soldiers and Ugandan rebels. 

Some elements in Khartoum continue to sponsor Uganda's rebel Lords Resistance Army in an attempt to destabilise the south and so undermine the road to the promised 2011 referendum on independence. 

"There is nothing more dangerous than young men with no jobs and a gun," said Egeland. "We have to avoid conflicts re-emerging, and for that, support is very much necessary. Sudan cannot do it alone. With no money it will all collapse."

Donor countries have funded less than one-fifth of this year's humanitarian relief operation in southern Sudan, forcing even food rations to be cut.

When the Bor Dinka's barge finally reaches its destination, there are tearful reunifications. Brothers and sisters fall to their knees in ecstatic embraces. "I'm so happy I could fly," says 35-year-old Martha Nyanwut upon seeing her sister-in-law for the first time in a decade - forgetting for a moment the myriad of challenges that await her.