The theme of Kanthapura is the unification of different Indian castes under a Gandhian system of social justice during the fight against British rule of India. At the beginning of the novel, Kanthapura, a rural Indian village, is divided by caste. The narrator says of the Pariah neighborhood, where the people of the lowest caste live, "Of course you wouldn't expect me to go in the Pariah quarter" (page 5). The narrator is herself prejudiced against the Pariahs.
The village lives in its traditional way until Moorthy, a member of the Brahmin caste, goes to the city and returns with the ideas of Gandhi. As the narrator says of Moorthy, "he is one of these Gandhi-men, who say there is neither caste, nor class, nor family" (page 9). His fellow Brahmins are repulsed by his embrace of the Pariahs, and he begins to rally villagers to support the Indian National Congress and to wear homespun clothing in protest of the British occupation of India. The authorities eventually crack down on the villagers, and Moorthy is jailed. Rangamma, a widow who Moorthy has befriended, organizes the women of the village to continue the protest, and they are unbroken, even in the face of brutal acts committed by the authorities. In the end, the villagers of all castes are united against British rule and hope for Indian independence. While fighting against British rule, the members of the village unite, regardless of their caste.
The most powerful themes from Rao's work come from the retelling the success and struggle of the Indian independence movement. This notion of struggle and perseverance is something that can be applied to both Gandhi and Moorthy in their attempts to bring about change to all of India. On a more literary level, I think that the theme of activism and seeking change is vitally important to the novel. The theme of action and being an active agent in one's own environment is an idea that resonates clearly in the work. Rao is deliberate in tying this into both literary and political threads. The women in the village are relegated into a role of political and social activity at the exposition of the work. The Status Quo does not favor their possession of political or social power. Yet, at great cost to them, the women show and display power and voice. Recognizing the need to protect their own dignity and senses of self, Rao shows that power and voice are ends that anyone can and should activate. It is this political idea that Gandhi advocated and a literary one that is explored in Rao's work.