The Conquest of Hispania: Scipio Africanus
The territory that was to become the Roman province of Hispania was originally held by the Carthaginians, and their native allies. The Carthaginians controlled the major port cities, and they had the leading Spanish chiefs on their payroll. This allowed them to collect mercenaries, train soldiers, and gather raw materials for their expanding Mediterranean Empire.
The Carthaginians wanted to control trade across the Mediterranean. They wanted to be like the Athenian Empire in the eastern Mediterranean. Carthage was a single city with farms and manors surrounding it. The city itself did not have many soldiers, but it's vast wealth allowed it to hire and maintain mercenary armies.
Carthage had a noble family that dominated politics. The house of Barcid contained many members of the Barca family, and it was they who conquered Hispania for the Carthaginian Republic. The Barca family realized early on that the Roman Republic was a danger to their city, and they fought against the Romans at every opportunity.
The Second Punic War
Hamilcar Barca led the Carthaginian armies in the First Punic War, and under his command the Carthaginians were defeated and driven from Syracuse. After this defeat he withdrew to Barcid Hispania to rebuild his armies, train his sons, and prepare for another war with Rome. It was Hamilcar's son, Hannibal Barca, that led the attack on Rome.
Hannibal crossed the Alps with a massive army and broke in to the Italian peninsula in a storm of violence. He crushed one Roman army after the other, but he could never use his victories in the field to achieve victory in the war. In Hannibal's early battles against the Roman Republic there was a young man in the Roman armies that changed the course of the war.
Publius Cornelius Scipio, better known as Scipio Africanus, survived the slaughter of the Roman armies in their early engagements with Hannibal. Scipio then followed his father to Hispania, not because they were fleeing Hannibal, but because Scipio saw a chance to defeat Hannibal strategically.
Conquest of Hispania
Scipio took command of the Roman armies in Hispania after the death of his father and uncle. Scipio trained his army, drilled them, and made them ready to move at a moments notice. He had a small fleet under his command as well. Scipio believed he could defeat Hannibal in Italy by breaking Hannibal's supply chain in Hispania.
Scipio's first move was a bold attack. While the Carthaginian armies were out in the field attempting to get the Romans to attack them, Scipio launched a brilliant two-pronged attack on the Carthaginian capital in Hispania. New Carthage was a large port, and the central hub of governance in the province. Scipio knew that if he could take it, he could outlast the Carthaginians in the field.
Scipio had a great grasp of tactics and strategy. His plan to take the city was two fold. His navy would encircle the port preventing any Carthaginian ships from warning anyone and using their marines to launch diversionary assaults. Further, his armies would launch a two part attack on the cities walls. Scipio used knowledge gained from local guides to determine that his army could attack across some marshland near the city when the tide went out.
This was Scipio's brilliance, he would hold the enemy in one place with a sustained assault, and then break them with an attack from another direction. The plan was a complete success and the cities defenders were routed.
New Carthage was well stocked and allowed the Romans to prepare for their next move. Scipio was generous in victory, and allowed the Spanish tribes to retrieve their hostages that the Carthaginians had been holding. Because of this, the Spanish tribes revolted against the Carthaginians, and joined with Scipio. Scipio was then ready to fight the Carthaginians and the Celtiberian tribes that still served with them.
Scipio brought his army to the field, and defeated two Carthaginian armies before they could group up. This victory forced Hasdrubal, Hannibal's brother in law, to withdraw from Hispania and take his forces to Italy. Meanwhile, Scipio took complete control of Hispania and after putting down several Spanish revolts began to turn his attention to invading Africa.
Henry, Liddell Hart Basil. Scipio Africanus: Greater than Napoleon. Cambridge, MA: Da Capo Press, 2006.
Goldsworthy, Adrian Keith. The Punic Wars. London: Cassell, 2000.