My father, Ben Obumselu, who has died aged 86, was a leading literary critic, a key figure in the Biafran war and, later, an influential political adviser in Nigeria. A combination of scholarship and political engagement informed much of his life.

He was among a formidable generation of university graduates in the mid-1950s poised to lead Nigeria at independence in 1960. At Ibadan University, where he studied English and classics, he was the first president of the National Union of Nigerian Students. Like his contemporaries, the writers Chinua Achebe, Wole Soyinka and Chris Okigbo, he was a protege of the pioneering professor of English Molly Mahood.

Ben was born and brought up in Oba, on the outskirts of Onitsha, on the banks of the river Niger, the son of Albert Obumselu, a builder and church organist, and his wife, Naomi (nee Azubuike). He attended Dennis Memorial grammar school in Onitsha.

After graduating from Ibadan University, he became assistant registrar at the West African Examinations Council in Accra and Lagos. He went to Oxford University in 1960 to work for a doctorate, and in 1963 returned to Ibadan to lecture at the university. When the Nigerian civil war began in 1967 he left for his home region in eastern Nigeria, joining the Biafran struggle. There, he had a variety of assignments including in intelligence, and as an adjutant general in the Biafran army. He was speech writer and special adviser to the Biafran leader Emeka Ojukwu, helping to write the Ahiara Declaration, setting out Biafra’s vision.

At the war’s end in 1970 he left Nigeria and worked in universities in Zambia, Congo, Malawi, Botswana and Swaziland, as a senior lecturer and professor, becoming a leading critic of postcolonial literature. He visited Mozambique and South Africa and in 1974 became John Cadbury fellow at the Centre of West African Studies, Birmingham University. An intellectual curiosity and restlessness informed his travelling, voracious reading and many friendships.

He returned to Nigeria in 1981 to serve as political adviser to the civilian governor of Anambra state, Jim Nwobodo, who had been a student of Ben’s at Ibadan University.

After the return of military rule in 1983, Ben went back into academia, working in universities in eastern Nigeria as a dean and senior lecturer. In 1999, when civil rule was restored, he moved into newspaper publishing and back into political activity. Though he avoided the limelight, he was widely respected and found himself drawn into Nigerian public life, becoming a leading figure in the pan-Igbo political organisation Ohaneze Ndigbo.

He was admired by many colleagues and ex-students, who published a book of essays in his honour.

His wife, Fidelia, survives him, along with the two children from their marriage, four children from his earlier marriage, to Christine Clinton, and two children from other relationships.