Both of these men were leaders of their community. Even though Okonkwo didn't rule by himself, he was still a very important man to his tribe. On the other hand, Oedipus was HUGE part of his community. He slayed the jinx and became king. Both men ruled differently also. This could be as a result of them coming from two different societies. Okonkwo ruled with a harsh hand because that was the thing to do when some one did something wrong.
Like true tragic heroes, these men have a fall from grace. When Oedipus fell, it was less obvious then when Okonkwo fell. Oedipus's fall began once he discovered that he killed his father and took over the thrown. He went into a deep depression and eventually gouged his eyes out. He eventually died of old age, but the end of his life was miserable. Okonkwo's fall was painfully obvious. The beginning of the fall was when he shot at his wife. The end concluded with Okonkwo hanging himself, because he couldn't take the Christianity any more.
It is ironic how both of these men's lives were good until some information was spread around that either tore them apart, ruined them, or both. Information getting to them is what led to the end of both Okonkwo and Oedipus. For Okonkwo it was Christianity. When Christianity moved into his area and started taking over, he just gave up. The information that the Christians were preaching, made so much sense that many people began to convert. This effected Okonkwo in a big way, especially when his own son converted. Eventually, after many failed efforts to stop Christianity, he hangs himself. Oedipus on the other hand never actually killed