THOMAS SANKARA was on Brian Peterson’s radar from Africa history classes in 1991 when, he tells me,  he seemed “a rare bright spot” in the African history of the 1980s.

Peterson’s first book investigated the Islamisation of southern Mali and  how a whole population switched religions during the colonial period. It involved the systematic gathering of oral histories but when he returned on sabbatical in 2012, the presence of jihadist groups made the work unsafe.

Switching his attention to Burkina Faso, he began a grassroots study of Sankara’s revolution and realised that there is neither a basic outline of  it or Sankara’s life. “Basic narrative and chronologies of major African figures haven’t been written, because historians avoid biographies. But a basic political biography of Sankara was essential.”