Symbols are objects, characters, figures, and colors used to represent abstract ideas or concepts.
Achebe depicts the locusts that descend upon the village in highly allegorical terms that prefigure the arrival of the white settlers, who will feast on and exploit the resources of the Igbo. The fact that the Igbo eat these locusts highlights how innocuous they take them to be. Similarly, those who convert to Christianity fail to realize the damage that the culture of the colonizer does to the culture of the colonized. The language that Achebe uses to describe the locusts indicates their symbolic status. The repetition of words like “settled” and “every” emphasizes the suddenly ubiquitous presence of these insects and hints at the way in which the arrival of the white settlers takes the Igbo off guard. Furthermore, the locusts are so heavy they break the tree branches, which symbolizes the fracturing of Igbo traditions and culture under the onslaught of colonialism and white settlement. Perhaps the most explicit clue that the locusts symbolize the colonists is Obierika’s comment in Chapter 15: “the Oracle . . . said that other white men were on their way. They were locusts. . . .”
Okonkwo is associated with burning, fire, and flame throughout the novel, alluding to his intense and dangerous anger—the only emotion that he allows himself to display. Yet the problem with fire, as Okonkwo acknowledges in Chapters 17 and 24, is that it destroys everything it consumes. Okonkwo is both physically destructive—he kills Ikemefuna and Ogbuefi Ezeudu’s son—and emotionally destructive—he suppresses his fondness for Ikemefuna and Ezinma in favor of a colder, more masculine aura. Just as fire feeds on itself until all that is left is a pile of ash, Okonkwo eventually succumbs to his intense rage, allowing it to rule his actions until it destroys him.