Sudan is the largest and one of the most geographically diverse countries in Africa. Mountain ranges divide the deserts of the north from the swamps and rain forests of the south, and the River Nile splits the country from east to west.
The country has been beset by conflict. Two rounds of north-south civil war cost the lives of 1.5 million people, and a continuing conflict in the western region of Darfur has driven two million people from their homes and killed more than 200,000.
Sudan's centuries of association with Egypt formally ended in 1956, when joint British-Egyptian rule over the country ended. Independence was rapidly overshadowed by unresolved constitutional tensions with the south, which flared up into full-scale civil war that the coup-prone central government was ill-equipped to suppress.
The military-led government of President Jaafar Numeiri agreed to autonomy for the south in 1972, but fighting broke out again in 1983. After two years of bargaining, the rebels signed a comprehensive peace deal with the government to end the civil war in January 2005.
The accord provides for a high degree of autonomy for the south. The region will also share oil revenue equally with the north.
In Darfur, in western Sudan, the United Nations has accused pro-government Arab militias of a campaign of ethnic cleansing against non-Arab locals. The conflict has strained relations between Sudan and Chad, to the west. Both countries have accused each other of cross-border incursions. There have been fears that the Darfur conflict could lead to a regional war.
Decades of fighting have left Sudan's infrastructure in tatters. With the return of millions of displaced southerners, there is a pressing need for reconstruction. The economic dividends of peace could be great. Sudan has large areas of cultivatable land, as well as gold and cotton. Its oil reserves are ripe for further exploitation.
Arabic is the official language and Islam is the state religion, but the large non-Arab, non-Muslim minority has rejected attempts by the government in Khartoum to impose Islamic Sharia law on the country as a whole. President Omar Bashir has been locked in a power struggle with Hassan al-Turabi, his former mentor and the main ideologue of Sudan's Islamist government. Since 2001 Mr Turabi has spent periods in detention and has been accused, but not tried, over an alleged coup plot.
Mr Bashir faces two international arrest warrants - issued by the International Criminal Court in The Hague - on charges of genocide, war crimes and crimes against humanity. The charges relate to the conflict in the western Darfur, where thousands of people died of violence, disease and displacement during the fighting between government and rebel forces.
He has dismissed the allegations and has continued to travel to countries which oppose the indictment.
Overview
Sudan has been at war with itself for almost its entire post-colonial history, starting in 1956. Nearly all of its major ethnic and religious groups have fought one another, and politics continues to be dominated by mistrust, outside interference and combustible animosities. There are dozens of armed groups across the country.
Now the country is partaking in what could be the continent's biggest divorce. A long-awaited referendum on southern Sudan’s independence, set in motion by a 2005 peace agreement to stop one of Africa’s worst civil wars, is scheduled for Jan. 9, 2011. The south is expected to vote by as much as 99 percent for secession, splitting the largest country in Africa in two and taking with it most of Sudan’s oil. Such a result could bring an end to the nearly one-million-square-mile experiment called Sudan, which for many troubled decades served as a bridge between the Arab and African world.
As the clock counts down toward voting day, despite earlier prognostications of a delay, there are more and more signs that things will go smoothly. The stakes are so high that neither side, the Islamist northern government or the former rebels who lead southern Sudan, seems to want to be sucked into a war again, or at least to start one.
Since the peace treaty was signed in 2005, the south has been semi-autonomous, running most of its own affairs. Southern Sudan is different culturally and religiously from the northern part of the country, a contrast between Arab and Muslim influences in the north and animist and Christian beliefs in the south.
The southern leaders have rebuilt towns and invested hundreds of millions, perhaps even billions, in roads, ministries, schools and factories, much of which could be bombed into oblivion in a few days by the north’s growing air force. To keep their dreams of independence alive, the southerners seem ready to make concessions. This includes sharing the oil.
Sudan's Explosive History
In 2005, the country's opposing political parties signed a peace accord that ended Africa's longest-running civil war, which killed an estimated 2.2 million people - 10 times as many as in Darfur. The perennial question is whether the relatively small group of Arabs who live along the northern reaches of the Nile and have historically ruled Sudan will share power and wealth in one of the most diverse populations on the continent. It was political exclusion that drove rebels in the semi-autonomous south to fight, and the same issue inspired the rebellion to the west, in Darfur, which has claimed an estimated 300,000 lives and blown up into one of the world's worst humanitarian crises.
The peace treaty between the north and the south, which American officials helped broker and the Bush administration considered a foreign policy triumph, was supposed to address these center-versus-periphery problems head-on. For the most part, the agreement has stopped the killing in the south, which during the 1980s and 1990s became a wasteland of burned villages, slave raiders and thousands of boys - the famous Lost Boys - trudging through the bush looking for a way out.
North-south tensions go back decades, to even before Sudan's independence in 1956. The north is mostly Muslim and historically has identified with the Arab world, while many southerners are Christian and more connected to Kenya, Uganda and other sub-Saharan nations. Beyond that, there is a huge divide when it comes to development, spawned by years of inequality.
While Khartoum has its luxury hotels and shopping malls, the south is where the roads stop. Flying over it, all you see is miles and miles of emerald green. The streets of the south's biggest cities are boulevards of mud. Children go to school under trees.
Two years after the peace treaty, much of the south was heavily militarized. The reason has been that the north has grown dependent on the oil from the south and if the south secedes, the north stands to lose billions of dollars yearly.
Both the north and south have said they want to avoid another costly war, and leaders from the two sides acknowledged that they need each other - the south has most of the country's oil and the north has most of the infrastructure. But the two sides were deadlocked over the toughest issues the treaty was supposed to solve: how to draw the north-south border, how to reform a very militarized government (the standard children's school uniform in Khartoum, the capital, is camouflage fatigues), and how to split Sudan's booming oil profits.
In July 2009, an international tribunal redefined the borders of the disputed oil region by splitting the contested zone between the two sides. In its ruling, the tribunal, seated at the Permanent Court of Arbitration in The Hague, overruled a decision by an international commission that Sudan's government rejected four years earlier. The ruling gives the north uncontested rights to rich oil deposits like the Heglig oil field, which had previously been placed within the Abyei region, which sits on the border between north and south. But the decision leaves at least one oil field in Abyei and gives a symbolic victory to the Ngok Dinka, an ethnic group loyal to southern Sudan and likely to vote to join it in a referendum.
