For more than a decade, an obscure civil war has ravaged the Sudan. Largely ignored by the rest of the world, it is Africa’s longest war, paralyzing the Sudan’s three southern provinces intermittently from 1955 and continuously from 1963. The war has led to perhaps a half-million deaths and has forced 200,000 southerners to flee for refuge in neighboring countries. All the terror and turmoil have come from cultural hatred.

A visitor can catch the meaning of the war on a Saturday night at the dance hall in Juba, the main town of the southern Sudan. As a southern quartet blares out its kinetic jazz, tall, bIack southerners and their callipygous women leave their opened bottles of “Camel” beer on metal tables and move toward the enormous dance floor, their legs suddenly beating, their rumps shaking with the first step on the floor.

A few young northern men, who work in the government offices of Juba, ask southern girls to dance. The northerners, a shade or two lighter in skin color, flail their arms and beat the steps. Their heads bob and their knees shake, but somehow they miss. They seem awkward, ill at ease, out of beat. In the words of the racial cliché, the northerners, though African, don’t have rhythm. Or, to be more accurate, they have a rhythm that is culturally different from that of the black southerners. Northerners look to the Middle East and Arabic culture; southerners to the heart of Africa and black culture.

The Sudan is the largest country in Africa, about a third the size of the United States, with a north of scrublands and sandy, arid hills, and a south of forests and grasslands. Swamps separate the two regions.

Of a population of 15 million, perhaps 11 million live in the north. Almost all of them are Moslem, most of them speak Arabic and many have some Arab blood. Most northerners wear robes called djellabahs and twisted turbans called immas; they live in rectangular adobe houses in walled compounds on ordered streets.

Most of the 4 million Sudanese in the south are pagans, though in the past missionaries managed to convert a half-million to Christianity. Some traditional southerners wear coiled bracelets of brass and bells on their ankles. Others carry spears and bows, and plaster their hair with rust-dyed cow hung. Many simply wear white shirts and Western trousers. Most southerners live in clusters of thatched, beehive huts.

The southern rebels call themselves Anyanya, which in Bari, a vernacular of the region, means a poison made by grinding the head of a cobra into powder. They want some degree of autonomy from the northern-run Sudanese Government in Khartoum. In principle, the government agrees. Soon after coming to power in 1969, President Jaafar el Numeiri promised the south regional autonomy, but so far he has failed to fulfill the promise. Recently, there have been a few promising signs, but the war and its brutality go on.

The issues are complicated by the long, ambiguous, and complex history of the South’s relations with the north. The two areas were not ruled as one until both were conquered by Muhammad Ali, the Khedive of Egypt, in 1820. Under Egyptian rule, a slave trade developed, with the Arabized traders of the north raiding the blacks in the south. This trade, which did much to alienate southerners from Islam and from their northern neighbors, is still brought up today by angry rebels.

During their colonial rule in the 20th century, the British cut the south off from the north, trying to shield it from Islam. The British even kept out Muslim traders and banned the sale of turbans and djellabahs. The south was opened to Christian missionaries. The missionaries were hampered by climate, lack of funds, the backwardness of tribes, and the tendency of the British to ignore the south. Though they did effect a good many conversions, they failed of their social goals. By independence in 1956, the mission schooling had failed to keep pace with the Islamic and government schooling of the north. The south was also far behind in political and economic development.

Southerners were kept out of the conferences that negotiated independence, and most of the posts in the new, independent government went to northerners. This imbalance provoked a mutiny by the southern-manned Equatoria Corps of the army in 1955. At least 260 northerners and seventy-five southerners were killed in this first violent protest by the south.

The constitutional committee, on which the south was allowed only three of the forty-three seats, rejected a federal system, and the southerners felt further aggrieved at having been cheated of their autonomy. The enmity was intensified after 1958, when Gen. Ibrahim Abboud took over the government and decided to deal with the south by converting it to Islam - by force, if necessary. Abboud opened Koranic schools in the south, sent down Islamic preachers, made Arabic the language of instruction in all schools, proclaimed Friday the day of rest, arrested priests, and finally expelled all missionaries. It was during this period that southerners began to flee across the borders. The Anyanya emerged in 1963.

After Abboud had been overthrown by civilian demonstrations in 1964, peace seemed possible. In 1965, leaders of the northern political parties and the southern exile organizations met in Khartoum. But the conference failed, probably because the rightist Islamic parties that controlled the government feared that autonomy for the south would be the first step toward separation.

The civilian government intensified the northern attempt to suppress the rebellion by force. There were massacres. On July 8, 1965, Sudanese soldiers began firing into the native huts of Juba. The shooting continued until the afternoon of the next day and left 360 southerners dead and many others wounded. Later, the soldiers rushed to the Juba hospital and killed a southern doctor who was trying to care for the wounded.

A few days later, a party of 100 southerners, including several government officials, were celebrating the weddings of two couples in a private home in the southern town of Wau. Suddenly, soldiers surrounded the house, opened fire, and then rushed in, still shooting. More than seventy southerners were killed, including a 4-year-old boy and a 10-year-old girl. These massacres increased the flight of southerners from the Sudan; some southern towns were almost stripped of their population.

When Numeiri came to power after his coup in 1969, he in turn intensified the military suppression of the rebellion. At the same, he promised the south regional autonomy and economic development, hinging his promises, however, on conditions: peace and the creation of a Socialist-minded class in the south. For more than two years, there has been little progress toward peace.

Most outsiders believe the Anyanya numbers 5,000 to 8,000 soldiers. Though there are splinter groups and rivals among the rebels, it is thought that, in, general, they are well organized, operating in large units with typewritten orders, radio communication, some semblance of uniforms and medical teams. It seems that their only significant outside help comes from the Israelis, who drop arms and other supplies from a DC-3 on a regular flight from Ethiopia.

Like most guerrilla groups in Africa, the Anyanya operate sporadically. They lay mines, ambush Sudanese patrols, shoot mortars at river boats, attack small outposts, steal food, and intimidate southerners who cooperate with the government. The vastness of the three provinces of the south is on their side. Government control is fragile in the hinterland of most of Africa. Thus, the rebels have managed to limit Sudanese control to those towns and villages that the government garrisons with soldiers or police. Given the expanse of territory and the size of the Sudanese army, few places can be so held. In Equatoria, the most southern and troublesome province, for example, the Sudanese are said to control only Juba and four other towns and villages.

The absence of government troops, however, does not mean that the Anyanya control, at least not in a formal way. The rebels work only in hiding. If they were to proclaim control over any sizable village, they would be blasted out by the Sudanese army and air force.

Most diplomats in Khartoum believe that the Sudanese army no longer launches brutal reprisals as it did in 1965, though nervous Sudanese soldiers probably still fire at any southerner they see running from them. Since Numeiri took over the government, there has been an attempt, in the diplomatic view, to discipline the troops and to use them only for convoy duty and to attack obvious rebel strongholds. As evidence, observers cite the rising populations in the towns of the south that were deserted after the 1965 massacres. But this picture of moderation and restraint has been disputed by Allan Reed, a young Anyanya sympathizer from La Habra, Calif., who has spent ten months with the rebels in the south, probably longer than any other foreigner. Reed, who trekked 3,000 miles with the Anyanya, came to the Sudan after Numeiri took over. In a series of interviews with the Los Angeles Times, Reed said that the northerners bomb villages, burn crops and huts, force villagers into the garrisoned towns, seize hostages, and kill them in reprisals. Reed also said that he has evidence of massacres since 1969 that resemble on a smaller scale the killings in 1965.

The Sudanese army and air force have several hundred Soviet advisers, perhaps as many as 700. But Western diplomats in Khartoum doubt some published reports that the Russians take part in Sudanese patrols or fly Russian helicopters in combat. Instead, they believe the Russians in the south limit themselves to planning, training, maintenance of the helicopters, and noncombatant flying.

There is some evidence that President Numeiri may finally try to put in effect some kind of autonomy for the south during 1972. After a succession of coup and counter-coup that ousted him from power for three days in July, Numeiri received a delegation of twenty southern leaders, including officials working for the Sudanese Government. They told Numeiri that peace could be restored in the south if he gave it autonomy soon - and, at the same time, opened negotiations with Joseph Lago, commander .of the Anyanya.

According to a member of the delegation, Numeiri agreed to both proposals. First, he conveniently blamed his past failures on the Communists, now in disgrace because of their role in the abortive coup against him. He told the southerners that autonomy had been held up by the Communist, Joseph Gareng, who had been minister of southern affairs until his execution after the July coups. Numeiri said that the Revolutionary Command Council, which runs the Sudan, had ordered Gareng to establish autonomy, but “he slipped everything we gave him into the drawer.” With Gareng gone, Numeiri said, autonomy would be included in the new Sudanese constitution, now being drafted and scheduled for adoption next year. At the same time, Numeiri promised that he would be willing to meet Lago at any time at any place to negotiate a settlement of the civil war.

The promises of Numeiri could mean an end to the war at last, but southerners seem far from euphoric. Rhetoric has a way of obscuring reality in the Sudan, and promises a way of hanging on as promises. Inertia often rules. Moreover, there are contradictions in the rhetoric. In mid-September, Numeiri flew into Juba and addressed a rally in the public square. He promised autonomy with “all authority in the hands of southerners, including a pure southern police force.” But he did not mention negotiation with the Anyanya at all. In fact, his words were hardly conducive to any kind of dialogue. Referring to the rebels, Numeiri said, “The door is open to anyone, but anyone who raises one rifle against us will have twenty rifles raised against him.”

To a large extent, an end to the war probably depends on the attitude of northerners and their understanding of the grievances, problems and differences of the southerners. In many ways, the northerners look on the southerners in the same manner that European colonizers looked on Africans in the past (and as the Portuguese still do). In Khartoum, southerners can be seen mostly in coolie labor, transporting huge sacks on their backs or sweeping stores or digging ditches. In the south, the top jobs go to northerners who administer the government there, just as the British officers did years ago.

To a Moslem of the north, especially one imbued with Arab culture, the people of the south hardly seem worth worrying about. In a recent interview, for example, Mahdi Mustafa, who heads the committee drafting the new constitution, said that he would see nothing wrong if the constitution proclaimed Islam the state religion of the Sudan. He said he recognized that southerners would not like the idea. “But,” he went on, “can we convince 11 million northerners that they should surrender their traditions for the benefit of a minority of a few hundred thousand?”

When I protested that the south had a population of 4 million, not a few hundred thousand, he replied, “Yes, but three and a half million are pagan. They have not seen any of the heavenly religions.” They did not count.

Mr. Meisler, Africa correspondent of the Los Angeles Times, is a frequent contributor to The Nation.