How does Okonkwo's exile connect to the deterioration of his village ?

While Okonkow was gone, his village changes. The Europeans have destroyed the Igbo framework that gave Okonkwo his validation, and they have destroyed the villages and people who stood in their way. Missionaries have arrived, built a church, and converted a number of the villagers..... even Nwoye, Okonkwo's son, embraced the new faith. Religion has divided the people. Okonkwo returns to a far different place than the one he left, but had he stayed, he would have fought the changes..... and in the process saved the Igbo traditions.

"The white man is very clever. He came quietly and peaceably with his religion. We were amused at his foolishness and allowed him to stay. Now he has won our brothers, and our clan can no longer act like one. He has put a knife on the things that held us together and we have fallen apart"