White men are first mentioned in this story in Chapter Fifteen, when Okonkwo is in his second year of exile. Obierika brings him news of a neighbouring tribe where white men have arrived, and, as a result, the entire tribe has been destroyed. He tells Okonkwo the tale of Abame an how it was wiped out. A white man arrived there to the amazement of the people, and eventually they consulted their Oracle to learn more about him:
The elders consulted their Oracle and it told them that the strange man would break their clan and spread destruction among them.
As a result, the people of Abame killed the white man. Later, however, three white men and other men returned, waited until everybody was in the market, and opened fire, slaughtering everybody accept for those who were sick or elderly, or those few who managed to escape. Obierika comments to Okonkwo that "A great evil has come upon the land as the Oracle had warned," and it is clear that white men are automatically linked with evil, the breaking of the tribe and destruction in this novel.
The white men are first seen in chapter fifteen.