With the defection of several cities to Carthage in Lucania, Bruttium, Apulia and Samnium after Cannae, Hannibal sent Mago Barca into Lucania with a detachment of troops in 216 BC to recruit troops and subjugate towns. Mago completed his mission, and when he sailed to Carthage to report to the Carthaginian senate and ask for reinforcements, Hanno was left in command of his army.
After several cities in Lucania, Bruttium, Apulia, and Samnium switched allegiance to Carthage following Cannae, Hannibal dispatched Mago Barca with a contingent of troops to recruit soldiers and subjugate towns. Hanno was left in command of the army after Mago completed his mission and sailed to Carthage to report to the Carthaginian senate for reinforcements.