One theme of the novel is that inability to adapt to changes can lead to one's downfall. This is shown in the conclusion, when Okonkwo hangs himself rather than submit to the laws of the British again. He has struggled with the clash of cultures ever since the missionaries built a church in Umuofia. He often ridiculed those who joined, and disowned his son Nwoye when he turned to the church as well. But Okonkwo was still subjected to the laws of the British. Whether this was just or unjust is another matter-Achebe here is highlighting the tragedy of obstinacy.
The novel ends with an ironic comment on Okonkwo's death by the District Commissioner, who sets out to write a book about the Ibo. He is racist, condescending, and describes the villagers as uncivilized and in need of pacification. The gravity of Okonkwo's suicide is lost on him, which makes the act even more tragic.
At the end of the novel, Okonkwo kills two British messengers and realizes that Umuofia will not go to war. In the last chapter, the District Commissioner arrives at Okonkwo's compound to discover that Okonkwo has hanged himself. Since suicide is considered an abomination in the Igbo culture, Okonkwo will not be given the funeral he deserves. Obierika blames the white men for Okonkwo's death, and the court messengers cut down his body from the tree. As the District Commissioner is walking away, he thinks about recording Okonkwo's suicide as an anecdote in his work, which is titled The Pacification of the Primitive Tribes of the Lower Niger.
One of the underlying themes throughout the novel concerns the ignorance and prejudice of European colonizers. Achebe had written the novel in response to Joseph Conrad's Heart of Darkness, which depicted Africans as unintelligent savages who lacked culture. Throughout Things Fall Apart, Achebe challenges traditional European perspectives of Africans by illustrating the rich culture of Igbo society. The final scene of the novel depicts the District Commissioner's prejudice and ignorance. His lack of concern and comments about Okonkwo's death reveal the prejudiced views of Europeans that Achebe hoped to challenge throughout his work.