Battle of Cannae - Prelude

Prelude

In the spring of 216 BC, Hannibal took the initiative and seized the large supply depot at Cannae in the Apulian plain. He thus placed himself between the Romans and their crucial source of supply. As Polybius notes, the capture of Cannae "caused great commotion in the Roman army; for it was not only the loss of the place and the stores in it that distressed them, but the fact that it commanded the surrounding district". The consuls, resolving to confront Hannibal, marched southward in search of the Carthaginian general. After two days’ march, they found him on the left bank of the Aufidus River and encamped six miles (10 km) away.

Reportedly, a Carthaginian officer named Gisgo commented on how much larger the Roman army was. Hannibal replied, "another thing that has escaped your notice, Gisgo, is even more amazing—that although there are so many of them, there is not one among them called Gisgo."

Consul Varro, who was in command on the first day, is presented by ancient sources as a man of reckless nature and hubris, and was determined to defeat Hannibal. While the Romans were approaching Cannae, a small portion of Hannibal's forces ambushed the Roman army. Varro successfully repelled the Carthaginian attack and continued on his way to Cannae. This victory, though essentially a mere skirmish with no lasting strategic value, greatly bolstered the confidence of the Roman army, perhaps to overconfidence on Varro's part. Paullus, however, was opposed to the engagement as it was taking shape. Unlike Varro, he was prudent and cautious, and he believed it was foolish to fight on open ground, despite the Romans' numerical strength. This was especially true since Hannibal held the advantage in cavalry (both in quality and numerical terms). Despite these misgivings, Paullus thought it unwise to withdraw the army after the initial success, and camped two-thirds of the army east of the Aufidus River, sending the remainder of his men to fortify a position on the opposite side. The purpose of this second camp was to cover the foraging parties from the main camp and harass those of the enemy.

The two armies stayed in their respective locations for two days. During the second of these two days (August 1), Hannibal, aware that Varro would be in command the following day, left his camp and offered battle. Paullus, however, refused. When his request was rejected, Hannibal, recognizing the importance of the Aufidus' water to the Roman troops, sent his cavalry to the smaller Roman camp to harass water-bearing soldiers that were found outside the camp fortifications. According to Polybius, Hannibal's cavalry boldly rode up to the edge of the Roman encampment, causing havoc and thoroughly disrupting the supply of water to the Roman camp.