Battle of Herdonia (210 BC) Flaccus and Gn. Fulvius Centumalus). Some state that there was just one battle in fact, but there is no general agreement on this issue. Following his incursion into southern Italy in 217 BC, Hannibal defeated the Roman forces in the battle of Cannae (216 BC). This victory brought him a host of new allies from Campania, Samnium, Apulia, Lucania, Bruttium and Magna Graecia, who revolted from Rome enticed by his narrative of Roman oppression. One of these allies was the city of Herdonia in northern Apulia. It was the site of a general engagement between Hannibal and the Romans already
Early Middle Ages had broken down, and the Roman army comprised mainly barbarians and soldiers recruited for a single campaign. The general decline in discipline also led to the use of smaller shields and lighter weaponry. Not wanting to share the glory, Eastern Emperor Valens ordered an attack on the Therving infantry under Fritigern without waiting for Western Emperor Gratian, who was on the way with reinforcements. While the Romans were fully engaged, the Greuthung cavalry arrived. Only one-third of the Roman army managed to escape. This represented the most shattering defeat that the Romans had suffered since the Battle of Cannae (216