Hanno, son of Bomilcar, was a Carthaginian officer in the Second Punic War (218 to 201 BC), and nephew of Hannibal Barca, Carthage's leading general. Hanno's mother was one of Hannibal's three elder sisters. When Hannibal's army reached the Western bank of the Rhône River they began preparations to cross. A group of Gauls gathered on the Eastern bank, intent on preventing the army from crossing. Hanno led a small group north to cross. The group crossed in small rafts they built. Once across they headed south toward the Gauls. Hanno sent a smoke signal to inform Hannibal that Hanno's force was ready. Hannibal began to send his cavalry across in canoes. As the cavalry attained a foothold on the Eastern bank, the Gauls approached, ready to fight. At this point Hanno's force attacked the Gauls' rear causing enough confusion to force the Gauls to retreat.
At the Battle of Cannae Hanno led the Numidian cavalry on the right (northern) side of the Carthaginian army. Hasdrubal led the Spanish and Celtic cavalry on the left (south near the Aufidus river) of the Carthaginian army. Hasdrubal was given about 6,500 cavalry, and Hanno had 3,500 Numidians. Hasdrubal's force was able to quickly destroy the Roman cavalry (on the south), pass the Romans' infantry rear, and reach the Roman allied cavalry while they were engaged with Hanno's Numidians. Once the Romans' allied cavalry was destroyed, Hanno and Hasdrubal were able to lead both cavalries into the Roman infantry's rear.