What are three important events that occurred in Part 2?

The exile: Okonkwo and his family move to his mother's village, Mbanta, to begin his seven-year exile for the accidental killing of Ezeudu's son. Okonkwo's family gives him a plot of land and the necessary seed-yams to start his own farm, but Okonkwo is deeply depressed and takes no pleasure in the work. He had been a leading man in Umuofia, with wealth and prestige. Circumstances have now forced him to start over, literally "from scratch," back with his mother's family as if he were still a child.

The white men in Abame: The first white man appears in the region, riding a bicycle into the village of Abame. The villagers are terrified; they consult their oracles, which warn that this man is a harbinger of destruction. The villagers kill the white man to ward off this evil, but more white men come, round up the villagers, and shoot them all—causing the exact destruction the villagers had sought to prevent. Okonkwo receives this news from his friend Obierika, who has come to Mbanta to visit with him. Neither of them knows what to make of the story, but both are sure that no such thing could ever happen in Umuofia.

Nwoye's conversion to Christianity: A few years after the events in Abame, while Okonkwo is still in exile, Obierika comes to tell him that white missionaries have arrived in Umuofia, and that people are beginning to convert to the new religion. While the consensus in Umuofia is that the converts were the "worthless" members of the community—low-status persons whose conversion is unimportant—Obierika was troubled to discover that Okonkwo's son, Nwoye, has also joined the missionaries. Given Okonkwo's previous status as a leading man of the village, Nwoye's conversion to Christianity is potentially much more disturbing to the community than the conversion of low-status individuals. On a more personal level, Obierika is dismayed on his friend Okonkwo's behalf. By choosing to align with the missionaries, Nwoye is rejecting the traditions of the Igbo and by extension, his father, who values those traditions. When Obierika confronts Nwoye about this and invokes Okonkwo in a sort of "what would your father think about this?", Nwoye explicitly rejects Okonkwo himself, saying "He is not my father." The unravelling of Igbo culture has begun, and is signified by this son rejecting his father.