The major driving force early in the story is Okonkwo's incredible drive for success and his hard work and success as a warrior and a man. He adopts a child from a neighboring village Ikemefuna and begins to care deeply for him, but his life is eventually demanded by the Oracle. Okonkwo cannot bring himself to participate in the killing of the boy.
Thanks to other violent actions brought about mostly due to Okonkwo's incredible temper, he is eventually banished and forced to live in another village. While he is gone, the white man and Christianity come to the Igbo, creating an incredible conflict with the traditional ways.
In a curious twist of events, Okonkwo returns and becomes the most staunch defender of their traditional ways. He goes so far as to kill a messenger from the court and try to stir up the Igbo to rebellion against the white powers. This leads to his suicide and the loss of any respect or power because of this crime against the traditional ways.