Mixing science and literature, the author narrates the true story of a war that happened at the end of the 19th century in Canudos, a settlement of Bahia's Sertão ("backland"), an extremely arid region where, even now, struggles against poverty, drought and political corruption continue.

Influenced by theories like positivism and social Darwinism from the end of the 19th century, Cunha discussed the forming of a new Brazilian republican nation and also its racial composition and its promising future of progress and civilization.

2) "O Homem" (The Man) exposes the land's inhabitants and their race composition, explaining the individual by its phenotype and emphasizing the opposition between the coast and the backlands men.

3) "A Luta" (The Rebellion), which narrates the conflict between the republican army and the sertanejos who, despite being considered "racially degenerate", succeed in winning many battles, even though they lost the war.

Through their conflict with the Canudos commune, the forces of modernity and progress are revealed to be just as irrational as their supposedly "uncivilized" opponents and the legitimacy of the republic is shaken at its foundations.