The Carthaginians spent the winter of 207 and 206 BC once again recruiting amongst the locals for a final effort against Scipio. In the spring of 206 BC Mago and Hasdrubal Gisgo marched from Gades with between 50,000 and 70,000 infantry, 4,000 to 5,000 cavalry and 32 war elephants. Scipio also prepared for the final campaign in securing new recruits among local Roman allies. Weakened by the need to garrison so many new conquests, the Romans were left with only a small contingent of actual legionaries among 45,000 infantry and 3,000 cavalry. Despite this, Scipio was ready to put an end to the war in Spain and he marched to Illipa to meet the advancing Carthaginian army.
Because of Scipio's brilliant tactical ability his inferiority in numbers (and an army made up of mostly non Romans) didn't make a difference. Preparing for a single and final decidng battle Scipio positioned his forces to prevent a Carthaginian retreat to their base at Gades. Much like the tactics of Hannibal in Italy, Scipio set up a cavalry ambush and lured Mago to attack. Mago moved against Scipio believing he was in the superior position and the trap was unleashed. The Carthaginians were initially driven back but managed to recover and extend the battle over a course of a few days. As it continued both lines were arranged in similar patterns on the field, with the main infantry of both armies occupying the center, flanked by local tribesman. On the final day, Scipio rearranged his formation with the tribesmen in the middle flanked by regular legionaries.
Scipio launched his attack at first light, and caught by surprise the Carthaginians were overwhelmed. During the protracted battle the Carthaginians, who had gone without breakfast were certainly hungry and exhausted throughout the day, succumbed to the Roman onslaught. A heavy rain late in the day delayed the inevitable, but because Scipio had earlier cut off the retreat route to Gades, the entire force of Mago and Hasdrubal Gisgo was soon enveloped and destroyed. The battle was a great victory for Rome, and Scipio in particular, was assured greatness in history as one of the ancient world's greatest generals.
Fighting illness, Scipio continued the campaign against the remnants of Carthaginian resistance. Moving against Gades, Scipio's illness worsened and at some point many believed he had died. His troops had long been operating unpaid and the recent plunder from various expeditions roused them into a mutinous state. Believing Scipio was too ill, or perhaps even dead, to make good on payments, they revolted on the Sucro River in 206 BC. The mutiny was quickly quelled as Scipio recovered, payments were arranged and the ringleaders executed, and operations soon continued as normal.
By the end of the year, 206 BC, Gades was also captured and several Spanish tribes also fell under the Roman sword. Advance political arrangements were made with several African tribes to aid in the eventual invasion of Africa. By 205 BC, Mago, knowing the cause in Spain was lost, sailed from Liguria to Italy in an attempt to join with Hannibal but was subsequently defeated in Cisalpine Gaul much like Hasdrubal before him. All evidence of Carthaginian resistance was gone, and the Romans stood as the new masters of Spain. Scipio left the Roman garrison and returned to Rome to be elected Consul. From there, he continued on to Sicily to prepare for the invasion of Carthage itself on the African mainland. He proved his worth to Rome and fought a brilliant campaign in Spain. The only blemishes on his record, for which he would be furiously punished politically by Cato the Elder years later, were his failure to stop Hasdrubal from escaping to Italy, and the short-lived and uneventful mutiny in 206 BC. However, even though the final conquest of Hispania would take another 2 centuries, the campaigns of Scipio in the far west of Europe helped establish Rome as the ultimate power of the Mediterranean.