 This transformation occurred following the Romans' victory over the Gauls at the Battle of Clastidium and then Hannibal's final defeat at Zama.By 196 BC, Rome was master of the woody plains and soon displaced the Etruscans, dotting the region with bustling colonies, clearing the land, fighting the last rebel tribes and gradually imposing its own civilisation.The centuries of Roman domination decided forever the main aspect of the Po Valley.