why is okonkwo's return home not as successful as he had hoped?

Soon after Okonkwo's return, Mr. Brown pays him a visit. He has sent Nwoye, now called Isaac, to the teacher's college at Umaru; Mr. Brown hopes Okonkwo will be pleased by the news. Okonkwo chases Mr. Brown away from his house, threatening the man with violence. The first rainy season after Okonkwo returns home, Mr. Brown leaves Umuofia due to failing health from overwork.

Okonkwo's return has not been as grand an event as he had hoped. The people are troubled by the new religion and new government; they are occupied completely with these changes. Okonkwo suffers, not only for personal reasons, but because he fears the clan is dying.