(The author spent two months this summer in Nigeria with Operation Crossroads Africa. He worked on the costruction of an open-air market in Ojo Village, twenty miles northwest of the capital of Lagos.)

THE BRUTAL civil war in Nigeria is slowly dragging to a close. Little remains of the secessionist Eastern Region--Biafra. In just a few months, probably, all rebel territory will belong to the Federal Republic. Even then, though, some fighting will continue. Guerrilla units are operating behind federal lines, and they have been since August.

These guerrillas will survive a few months, perhaps, after the capture of all rebel territory. Fear will move them and keep them dodging and fighting against a better-equipped and larger enemy. The rebel Ibo are convinced that defeat means death, both for soldier and civilian, but despite their desperate defense, death will come, as it has for most of their people.

In the political confusion after independence in 1960, political parties became firmly associated with regional and tribal groupings. In July, 1966, a group of army officers, dominated by members of the Hausa tribe, overthrew a federal government led by Ibo officers. Thus, when in September between thirty and forty thousand Ibos were killed in massive anti-Ibo riots in Hausa territory, the association between the massacres and government policy seemed obvious to leaders among the Ibo. Odumegwu Ojukwu, then the Governor of East Central State, which is Ibo, issued a call for all his tribesmen to return to the safety of their Eastern homeland, deported all non-Ibos, and seceded in May, 1967.

In the grisly drama of the war -- the atrocities, the starving masses, the jungle fighting -- rational thinking is overwhelmed by emotionalism. In the Western world cries of outraged morality for the arsenal of the press and public. The crisis in Nigerian seems a clear-cut case of the good guys versus the bad guys. The massacres in the North justify the Ibo cause and condemn the Lagos government. With self-righteous verbal overkill, defenders of Biafra cry that Lagos is waging a war of genocide.

WHILE THE WAR has its roots in tribalism, the baffling political history of Nigeria makes it impossible to point a finger of guilt at any particular group. When the British carved out their colonial empire in West Africa, they paid little attention to anything but economic and administrative expediency. Nigeria is an uneasy marriage of over two hundred tribal groupings, many with linked histories and cultural similarities, others with very different roots and ways of living. The Hausa-Fulani with about 29 million tribesmen dominate the North. Islam is their faith, and they trace their origins to the North and East of Africa.

The Yorubas in the West are largely Protestant and Catholic, and number about 9 million. The religious mixture of the Ibos in the East is about the same, but there are 12 million of them. Another five or six million Nigerians comprise a myriad of smaller tribes.

The three powerful groups--Hausa, Yoruba, and Ibo--have formed the major parties. Governments rose to power when two parties aligned against the other, and fell when the coalition dissolved and allegiances shifted.

After independence, though, a Yoruba-Ibo alliance coalesced into a single party opposing the Hausa. The numerical superiority of the North was one spur for the coalition, and, in fact, despite the coalition, the Hausa won a massive victory in the '64 elections.

The coalition, though, rested on more than a fear of numerical inferiority. Cultural differences heightened tribal suspicions.

According to the stereoyptes, Hausaman is religious, often illiterate, and traditional. Iboman is clever, hardworking, and ambitious; Yorubaman happy, sensitive, and warm.

THE stereotypes are, of course, just images, but the images are not entirely exaggerated. For both cultural and historical reasons, the North is the least developed section of the country. The bulk of the Nigerian army before the crisis was Hausa; for the uneducated the army is a road to advancement.

The Ibos in Nigerian history were a relatively insignificant tribe, but their society had achievement-based norms that adopted quickly to Westernization. All over Nigeria they formed a merchant and professional class. An engineer said, "If you are a businessman and you need engineers, you read applications and you don't look at tribes. Fifteen of the twenty men you hire will be Ibos."

The Yorubas fall somewhere in between, but closer to the Ibos than the Hausas. They are literate; they're politically sophisticated, but they look at life with a grin.

Thus, the Yoruba and Ibo came together not so much because they feared the numerical preponderance of the Hausa, for it would have been more politically expedient for either group to make peace with the Hausa against the other, but because they feared the political dominance of an uneducated majority. They could see the resources of the East and West financing the development of the North, and they envisioned hordes of inefficient Hausa bureaucrats.