This is of course a central issue for the entire story as the novel charts an African society rich in its own history, culture and religion and then observes how this disintegrates when Christianity and the foreign culture that accompanies it is injected into the scenario. Imperialism is basically presented as a clash of two civilisations in this novel, with the weaker of the two finally surrendering. Of course, a central element of imperialism is the way in which the white man assumes a natural sense of superiority and clearly believes that everything associated with the indigenous natives is "bad." Consider how Okonkwo answers Obierika's question about whether the white man understands their beliefs about land:
How can he when he does not even speak our tongue? But he says that our customs are bad; and our own brothers who have taken up his religion also say that our customs bad.
Imperialism is expressed through this natural sense of superiority and the way in which it is attached to the various tribal beliefs and practices of Ibo culture. Imperialism in the novel is associated with everything that is white being good and everything that is not being "bad" or backward.