The novel is set amongst the villages of the Igbo people in colonial Nigeria during the 1920s. Ezeulu is the chief priest of the god Ulu, worshipped by the six villages of Umuaro. The book begins with Ezeulu and Umuaro fighting against a nearby village, Okperi. The conflict is abruptly resolved when T. K. Winterbottom, the British colonial overseer, intervenes.

After the conflict, an indigenous African Christian missionary, John Goodcountry, arrives in Umuaro. Goodcountry begins to tell the villages tales of Nigerians in the Niger Delta who abandoned (and battled) their traditional "bad customs" in favour of Christianity.