Just as a peace deal has been signed between Sudan’s north and south, a new civil war has erupted in the country’s west. One million people have been driven from their homes and face death from starvation and disease in what the UN calls the world’s worst humanitarian crisis. What accounts for Sudan’s woes?

When it rains, it pours. The ugly politics of oil states have lately seized the limelight all over the world. A political meltdown in Venezuela. Terrorism in Saudi Arabia. Bloody insurgencies in Iraq. And now, Sudan.

The Sudanese civil wars did not start over oil. They started with the departure of the colonial powers – British and Egyptian – who made a last-minute decision to unify the largely Muslim north with the animist and Christian south. Many southerners had other ideas and launched a rebellion.

This was bloody – killing about 500,000 people. But perhaps not intractable. Israel, fearing for its survival and surrounded by hostile Arab powers, funded the southern rebels in an effort to weaken the Islamist north. But democratization in the 1960s brought some southerners into Sudan’s government. And in 1972 a peace deal was signed that gave the south a great deal of political autonomy and largely stopped the fighting.

That might have been the end of it, had Sudan not been afflicted by a series of great misfortunes.

The first of these was the Cold War. This took a small southern uprising in the early 1980s and helped turn it into a renewed civil conflict. Foreign funding created professional Sudanese guerillas, amply provisioned but without any real ideology, popular support, or even coherent goals. A Marxist dictatorship in Ethiopia, hoping to please its Soviet backers, was looking for ways to spread the “workers’ revolution.” A southern Sudanese warlord named John Garang stepped forward, declaring that his goal was to liberate the whole of Sudan from capitalist oppression.

This was mystifying to most southerners, who wanted nothing to do with the north, much less to liberate it. But Garang persisted, labeling entire opposition-controlled villages as “class enemies” needing to be eliminated. Backed by Ethiopian funds, training and arms Garang won increasingly important battles, wresting control of major southern towns from northern forces. Alarmed, the US began funding the north. Sudan was soon the second-largest African recipient of US aid.

The southern rebellion might still have faltered. But Sudan was suffering from another great misfortune – the rise of Islamic fundamentalism. The country attempted a breakneck modernization program funded by foreign loans during the 1970s. This was a disaster and by 1980 exports of key commodities such as cotton had actually fallen. Sudan became one of the most indebted countries on earth. Disoriented Sudanese – particularly the university-educated, now unable to find jobs – turned to extremist Islam for answers.

In 1983, just as Garang’s southern rebellion was getting under way, Sudan’s northern military dictator – locked in a power struggle with civilian political opponents – decided he could get the upper hand by creating an Islamic regime. He declared the imposition of Islamic law.

This had the unintended effect of unifying the divided southern rebels. They might not agree on Marxism, or Garang’s leadership. But one thing the southerners – mostly animists, a few Christians – could agree on was that they did not want to be part of any Islamic state. Southern factions from diverse ethnic groups unified to escalate the war.

And then the latest and greatest misfortune: the discovery of oil. As the 1983 war was getting started the US oil company Chevron was ramping up exploration at its Sudanese oil concessions – located in the country’s south. The oilfields were one of the rebels’ first targets. After the deaths of three employees Chevron quit the country.

But the oil war was just beginning. Suddenly the northern government’s goals changed. Forget political control – control of cities and commerce. The real money was now in oil. Thus the government’s overriding objective became to control the oilfields. The quickest way to do this was simply to get rid of the people. Aid workers reported flying over oil concession block 5A and seeing nothing but scorched earth and torched huts. Hundreds of thousands of southerners became refugees.

By the 1990s the Cold War was over. Ethiopia’s Marxist dictatorship was gone and with it John Garang’s funding. But the Sudanese government – with southern oilfields just coming online – was in no mood to talk peace. Instead it took advantage of Garang’s weakness to encourage splits in the rebellion. The southern fighters broke into two main groups – one receiving arms from the north – and began killing each other.

The northern government took advantage of the rebels’ feuds to continue depopulating the oilfields. The world got a front row seat to this in February 2002 when northern helicopter gunships opened fire on a crowd of thousands of civilians, mostly women and children, gathered to receive UN food aid.

The numbers of the dead can only be guessed at. But most estimates put the total civilian casualties in twenty years of Sudan’s civil war at over two million.

Yet the situation changed dramatically following the September 11th attacks. The northern Islamic regime – which had played host to Osama bin Laden – feared it would be a target and eagerly embraced a US-sponsored peace process. The north and south inked a deal giving the south political autonomy and half the oil revenues. This has for now brought an end to the north-south war.

But there is an unfortunate epilogue. The peace deal – with its generous splits of money and power – inspired other excluded groups to fight. Men of the Darfur region in western Sudan – many of them veterans of battles in the south – in February 2003 took up arms and attacked government army posts.

True to form, the northern government made no attempt to restore political control. Instead, it armed Arab militias to massacre or drive off the Darfur region’s population. As of this writing, some one million Darfur Sudanese are refugees, many in danger of starving to death.

As always with Sudan’s wars, there are no heroes, only ugly politics. The ethnic cleansing suits the Darfur rebels just fine – their ranks have been swelled by angry male refugees. And the northern regime is not particularly concerned about the loss of more of its population. The oil, not the people, is the most valuable resource.

The only hope for the refugees’ lives is pressure from the international community on the northern government to stop the massacres. And another peace deal, and more splits of power and wealth. And pray that a new deal does not inspire any further rebellions.

This article was originally published on Countryrisk.com, before I sold the website to Roubini Global Economics.