Researching the biography of a contemporary Nigerian cannot be easy. Access to so much of the primary material in book-famished Africa is difficult in itself, but when the subject of one’s research is as modest and private as Chinua Achebe the challenge is greater still.

There are also attendant risks in taking as one’s subject a living writer who can be expected, as he is not yet 70, to produce new important work.

By any standards, Achebe is one of the greatest novelists of this century.His first and most famous novel, Things Fall Apart, fundamentally changed attitudes to African literature, placing it on the world stage and allowing Achebe’s own generation to appraise its history with pride but not with sentimentality.

Subsequent books have been increasingly astringent examinations of a society which has allowed itself to degenerate into corruption and alienation, but always with the possibility of redemption through its inextinguishable humanity.

Achebe is a moralist without puritanism, a chronicler without pedantry, a satirist without rancour, and a tragic writer in an age of scepticism and uncertainty. In publishing terms his sales are phenomenal, accounting for a third of the turnover of the Heinemann African and Caribbean Writers Series, and thus sustaining the publication of many new authors whose work would otherwise have been too much of a financial risk.

In addition he is a poet, essayist and teacher, whose own work is taught more widely than any other African writer’s. He has been a broadcaster and ambassador: a man of parts, therefore, yet one who has eluded the gossip columns and retained a dignified privacy which must have been the despair of his biographer.

Ezenwa-Ohaeto’s is a thoroughly researched biography culled from contact with people all over the world who know Achebe, from old school and college records, from the archives of the Nigerian Broadcasting Service, from war reports, university citations, book reviews and, of course, the novelist’s own work.

The scholarship is assiduous, but slightly distancing. Ezenwa-Ohaeto lacks the skill of a Michael Holroyd or a Richard Holmes, who bring to their literary lives a combination of irony and passion which almost seems to make them flesh and blood. Ezenwa-Ohaeto deals in accurate description and judicious scholarly editing but has not yet developed the confidence of the great biographer who brings something of himself to the interpretation of his subject.

Take, for example, the death of Christopher Okigbo in the civil war. The loss of a close friend and the most original literary poet of his generation must have been a shattering blow to Achebe, but all we get of his grief is a chunk of an essay written some time later. The biographer stands back and lets the quotation do the work for him.

There are obvious virtues in this objectivity. The reader trusts the biographer. Achebe’s story is unfolded sequentially, accurately, sometimes movingly. It has been, after all, a dramatic life, combining sensational publishing success, confrontations with authority, international diplomacy,global conferencing and a paralysing car accident. At the centre of it, though not sufficiently woven into the whole tapestry, are Achebe’s five novels, Things Fall Apart, Arrow of God, No Longer at Ease, A Man of the People and Anthills of the Savannah.

I have always seen these books as five sections of one epic novel, each in different registers of English but collectively depicting the story of modern Africa. It is a tale in which the white man has a fairly dishonourable but in the end relatively minor role. What the biography fails to give us is a critically integrated account of this masterly fiction.

It does, however, provide us with the first detailed account of Achebe’s life and thus some explanation of his special gift of showing to his fellow Nigerians, and to the whole of Africa, examples of their self-inflicted decline - and some frail shoots of hope. In an essay I wrote several years ago, I asked if tragedy is possible in the modern world. Achebe proves that it is, and his biographer goes some way to revealing why he is able to do so.

Alastair Niven is director of literature at the British Council