Q&A: South Sudan independence
The people of South Sudan are preparing for independence after 99% of voters backed leaving Africa's biggest country in two, following decades of conflict with the north.
Why do most southerners want their own country?
Sudan's borders - like those in the rest of Africa - were drawn up by colonial powers with little regard to cultural realities on the ground.
South Sudan is full of jungles and swamps, while the north is mostly desert.
Most northerners are Arabic-speaking Muslims, while the south is made up of numerous different ethnic groups who are mostly Christian or follow traditional religions.
With the government based in the north, many southerners said they were discriminated against, and north and south have fought each other for most of the country's history. Southerners were also angered at attempts to impose Islamic law on the whole country.
What happens next?
The world's newest country will come into being on 9 July 2011 - exactly six years after the peace deal which ended the most recent north-south war took effect.
Then the hard work really begins.
The two sides must decide on issues such as:
- Drawing up the new border
- How to divide Sudan's debts and oil wealth
- Whether the new country will have its own currency
- What rights southerners will have in the north - and vice versa
- How vigorously the border will be enforced.
Is South Sudan ready for independence?
To be brutally honest, no.
After years of warfare and being ignored by central government, the country-to-be, which is larger than Spain and Portugal combined, has hardly any roads and not nearly enough schools or health services for its population of roughly eight million.
The SPLM former rebels who have been running the region since 2005 have at least gained some experience of governance.
They have lots of money from the south's oilfields but their critics say they have so far wasted much of it on the military and not done enough to raise living standards in one of the world's poorest regions.
Some also say the SPLM is dominated by members of South Sudan's largest ethnic group - the Dinkas - and accuse them of ignoring the demands of other communities, in particular the second largest - the Nuer.
The south's government has drawn up ambitious plans to develop its cities and has decided the winner of a competition to compose a new national anthem. The south's own flag is already on display across the region.
Is Khartoum going to accept the south's independence?
After the results of the referendum were announced, President Omar al-Bashir said Sudan would be the first country to recognise its new neighbour.
But since then there has been a lot of fighting in border regions, such as Abyei and South Kordofan, which even prompted fears that war could resume.
The two sides have now signed several peace deals but tension remains high.
The SPLM accuses Khartoum of funding at least seven separate rebellions in a bid to keep the new country weak and unstable - accusations it denies.
Although South Sudan is building close links with Uganda and Kenya, its relations with its northern neighbour will certainly be one of its more important diplomatic considerations for many years to come.
What will happen to the north?
The immediate priority for the northern government will be to keep hold of as much of the oil revenue as it can, as most oilfields lie in the south.
Khartoum has some leverage, as most of the oil pipelines flow north to Port Sudan on the Red Sea.
In terms of ordinary people's lives, both sides have agreed to let all Sudanese - in particular the many southerners in Khartoum - choose which nationality to take.
But President Bashir's announcement that he will implement a stricter version of Sharia in the north if the south secedes may prompt even more southerners to leave the north.
Both Sudan and the South are reliant on their oil revenues, which account for 98% of South Sudan's budget. But the two countries cannot agree how to divide the oil wealth of the former united state. Some 75% of the oil lies in the South but all the pipelines run north. It is feared that disputes over oil could lead the two neighbours to return to war.
Although they were united for many years, the two Sudans were always very different. The great divide is visible even from space, as this Nasa satellite image shows. The northern states are a blanket of desert, broken only by the fertile Nile corridor. South Sudan is covered by green swathes of grassland, swamps and tropical forest.
Sudan's arid north is mainly home to Arabic-speaking Muslims. But in South Sudan there is no dominant culture. The Dinkas and the Nuers are the largest of more than 200 ethnic groups, each with its own languages and traditional beliefs, alongside Christianity and Islam.
The health inequalities in Sudan are illustrated by infant mortality rates. In South Sudan, one in 10 children die before their first birthday. Whereas in the more developed northern states, such as Gezira and White Nile, half of those children would be expected to survive.
The gulf in water resources between north and south is stark. In Khartoum, River Nile, and Gezira states, two-thirds of people have access to piped drinking water and pit latrines. In the south, boreholes and unprotected wells are the main drinking sources. More than 80% of southerners have no toilet facilities whatsoever.
Throughout the two Sudans, access to primary school education is strongly linked to household earnings. In the poorest parts of the south, less than 1% of children finish primary school. Whereas in the wealthier north, up to 50% of children complete primary level education.
Conflict and poverty are the main causes of food insecurity in both countries. The residents of war-affected Darfur and South Sudan are still greatly dependent on food aid. Far more than in northern states, which tend to be wealthier, more urbanised and less reliant on agriculture.