As increasing numbers of Roman infantry entered the fray, Syphax's men were first held off and then broke and fled.
[6] In 219 BC Hannibal, the de facto ruler of Carthaginian Iberia, led an army to Saguntum and besieged, captured and sacked it.
[9] Hannibal led a large Carthaginian army from Iberia, through Gaul, over the Alps and invaded mainland Italy in late 218 BC.
[13] One of Carthage's allies in Spain was the Numidian prince Masinissa, who led a force of light cavalry in several battles.
Adjacent to territory where Carthage had a strong influence was an area controlled by a tribal alliance known as the Massylii, centred around the towns of Zama and Thugga.
[22][20] Scipio failed to win over Syphax,[22] who reaffirmed his support for Carthage and symbolised this by marrying Hasdrubal's daughter Sophonisba.
Hannibal was still on Italian soil; there was the possibility of further Carthaginian invasions,[30] shortly to be realised when Mago Barca landed in Liguria;[31] the practical difficulties of an amphibious invasion and its logistical follow up were considerable; and when the Romans had invaded North Africa in 256 BC during the First Punic War they had been driven out with heavy losses, which had re-energised the Carthaginians.
[32] Eventually a compromise was agreed: Scipio was given Sicily as his consular province,[33] which was the best location for the Romans to launch an invasion of the Carthaginian homeland from and then logistically support it, and permission to cross to Africa on his own judgement.
[37] Roman ships under Scipio's second-in-command, Gaius Laelius, raided North Africa around Hippo Regius, gathering large quantities of loot and many captives.
[38][36] Masinissa was contacted, he expressed dismay regarding how long it was taking the Romans to complete their preparations and land in Africa.
[40] Two large reconnaissance forces, consisting of both Carthaginians and Numidians were heavily defeated; the second because of the involvement of Masinissa's cavalry.
The city stood firm and a Carthaginian army under Hasdrubal set up a fortified camp 11 kilometres (6.8 mi) from the Romans with a reported 33,000 men.
[42] The presence of these two armies forced Scipio to lift the siege of Utica after forty-five days and withdraw to a strong position 3 kilometres (2 mi) away on a rocky prominence at Ghar el-Melh,[40] which became known as Castra Cornelia.
With his delegations Scipio sent junior officers disguised as slaves to report back on the layout and construction of the enemy camps.
[42] As the better weather of spring approached, Scipio made an announcement to his troops that he would shortly attempt to storm the defences of Utica and began preparations to do so.
Laelius's column attacked first, storming the camp of Syphax's Numidians and concentrating on setting fire to as many of their reed and thatch barracks as possible.
The camp dissolved into chaos, with many of its Numidian occupants oblivious of the Roman attack and thinking the barracks had caught fire accidentally.
[45][46] With no Carthaginian field army to threaten them, the Romans resumed their siege of Utica and pillaged an extensive area of North Africa with large and far-ranging raids.
[47] Upon being charged by the Romans and Masinissa's Numidians all of those Carthaginians who had been involved in the debacle at Utica turned and fled; morale had not recovered.
[59] Meanwhile, Masinissa's Numidians had pursued their fleeing countrymen under Syphax; accompanied by part of the Roman force, under Laelius.
[60] Syphax withdrew as far as his capital, Cirta, where he recruited more troops to supplement those survivors who had stayed with him on the retreat from the Great Plains.
These infantry were velites, younger men serving as javelin-armed skirmishers; they each carried several javelins, which would be thrown from a distance, a short sword and a 90-centimetre (3 ft) shield.
[59] The Roman Senate ratified a draft treaty, but because of mistrust and a surge in confidence when Hannibal arrived from Italy, Carthage repudiated it.
[67] Hannibal was placed in command of another army, formed of his and Mago's veterans from Italy and newly raised troops from Africa, with 80 war elephants but few cavalry.
[23][70] After the Romans had returned to Utica, Scipio received word that a Numidian army under Syphax's son Vermina was marching to Carthage's assistance.
[25] Masinissa exploited the prohibition on Carthage waging war to repeatedly raid and seize Carthaginian territory with impunity.
[77] In 149 BC, fifty years after the end of the Second Punic War, Carthage sent an army, under Hasdrubal the Boeotarch, against Masinissa,[note 3] the treaty notwithstanding.
The campaign ended in disaster at the battle of Oroscopa and anti-Carthaginian factions in Rome used the illicit military action as a pretext to prepare a punitive expedition.
[80] The Third Punic War began later in 149 BC when a large Roman army landed in North Africa[81] and besieged Carthage.
[82] In the spring of 146 BC the Romans launched their final assault, systematically destroying the city and killing its inhabitants;[83] 50,000 survivors were sold into slavery.