It seems that violence is part of the culture of Umuofia, and has become so ingrained that there are even ways in which violence becomes the mark of becoming a man and gaining status and prestige amongst the tribe. The whole incident of gaining Ikemefuna instead of waging war shows that violence is very much a part of Ibo society, and it is clear that Okonkwo himself, as the princple protagonist, gains quite a reputation through his own violent exploits, as the following quote demonstrates:
In Umuofia's latest war he was the first to bring home a human head. That was his fifth head; and he was not an old man yet. On great occasions such as the funeral of a village celebrity he drank his palm-wine from his first human head.
It is clear then that the Ibo culture has a clear relationship with violence and war that is very much a part of their lives, and is inherited by their children as part of the normal process of socialisation. However, it needs to be stressed that Achebe goes to great lengths to present the culture in this book as being one that is based around system and order. Whilst there are certain situations in which violent acts are praised, there are definitely others in which they are censured, as Okonkwo discovers to his cost when he beats his wife during the Week of Peace. It is impossible therefore to conclude that this is a tribe of ignorant and unrestrained savages. They act according to a moral code just as we do.