Answer: The conflict between Okonkwo and his father Unoka.
The conflict between Okonkwo and his father Unoka represents the theme of fate vs. free will. Okwonkwo hates his father deeply. He believes he is lazy and entitled. Moreover, he has a terrible reputation as a debtor around Umuofia. Okonkwo strives to be different than his father, and through free will, defeat fate. He, however, ends up becoming a callous, hardworking, but violent man.