As in the case of Chad, Sudan’s second civil war drew in an array of foreign players. Mengistu‘s regime in Ethiopia supported the cause of the southern Sudanese in retaliation for Khartoum’s support for Eritrean secessionists and Tigrayan rebels. In Libya, Gaddafi, who had once supported the Eritreans but who switched sides when Mengistu came to power, joined Mengistu in supporting the southern Sudanese. Numeiri meanwhile supported an anti-Gaddafi Libyan group, the National Front for the Salvation of Libya, which set up offices in Khartoum in 1981 and broadcast propaganda programmes attacking Gaddafi. Numeiri also gave assistance to anti-Gaddafi groups from Chad. The United States, for its part, despite the repression Numeiri unleashed in southern Sudan, invested heavily in his regime to bolster him as a counter-weight to Gaddafi and Mengistu, both of whom it regarded as pro-Soviet activists; US assistance to Numeiri totalled $1.5 billion.
With American support, Numeiri was confident he could deal with any threat posed by rebels in the south. But he was beset by a host of other difficulties. Hoping to establish Sudan as the ‘breadbasket’ of the Middle East, Numeiri had encouraged massive investment in mechanised agriculture, but the overall result was a decline in agricultural production and a foreign debt of $12 billion that Sudan had no means of repaying. When drought struck in 1983 and again in 1984, causing mass hunger, Numeiri, like Mengistu in Ethiopia, ignored the consequences, desperately trying to avoid jeopardising Sudan’s image as a suitable destination for agricultural investment. Only after an estimated quarter of a million people had died was he prevailed upon to take action. Forced by foreign creditors to accept austerity measures, Numeiri found his grip on power slipping. Shortages, inflation, unemployment, deteriorating social services and rampant corruption caused widespread discontent. The famine itself provided a rallying point for organised protest. A coalition of trade unions and professional groups, including lawyers, doctors and civil servants, led the opposition. When urban strikes, riots and demonstrations erupted, not even the army was willing to stand by Numeiri. In April 1985, after sixteen years in power, he was overthrown.
An election in 1986 brought to power northern politicians fully committed to the establishment of an Islamic state. As prime minister, Sadiq al-Mahdi, the leader of the Umma Party, pronounced himself in favour of ‘the full citizen, human and religious rights’ of non-Muslims. But he also declared: ‘Non-Muslims can ask us to protect their rights – and we will do that – but that’s all they can ask. We wish to establish Islam as the source of law in Sudan because Sudan has a Muslim majority.’ The sharia code introduced by Numeiri in 1983 remained in force.
Under Sadiq’s regime the north experienced many of the benefits of liberal democracy – parliamentary debate, a vigorous press, an independent judiciary, active trade unions and professional associations. But for the south there was unrelenting warfare. The SPLM refused to accept a ceasefire or to take part in the election, demanding a constitutional convention. Sadiq responded by arming Baggara Arab militias in western Sudan – murahalin – licensing them to raid and plunder at will in the Dinka and Nuer areas of Bahr-al-Ghazal, just as their forefathers had done in the nineteenth century. Dinka and Nuer villages were attacked and burned, their livestock stolen, their wells poisoned; men, women and children were killed or abducted and taken back to the north where they were traded or kept as slaves. Atrocities were commonplace. In revenge for an SPLM attack on a Rizeigat militia group in March 1987, Rizeigat survivors attacked Dinka men, women and children in the town of Al Diein in southern Darfur, setting fire to six railway carriages where they were sheltering, killing more than 1,000; those who were not burned to death were stabbed and shot as they tried to escape. A report on the massacre, written by two Muslim academics at the University of Khartoum, blamed the killing on the government. ‘Government policy has produced distortions in the Rizeigat community such as banditry and slavery, which interacted with social conflicts in Diein to generate a massacre psychosis … Armed banditry, involving the killing of Dinka villagers, has become a regular activity for the government-sponsored militia.’ Rizeigat militias, they said, made a practice of selling Dinka women and children to Arab families for use as servants, farm workers and sex slaves. ‘All this is practised with the full knowledge of the government.’