From the field of battle Hannibal had turned his steps to Campania, He knew Rome better than the simpletons, who in ancient and modern times have fancied that he might have terminated the struggle by a march on the enemy's capital. Modern warfare, it is true, decides a war on the field of battle; but in ancient times, when the system of attacking fortresses was far less developed than the system of defence, the most complete success in the field was on numberless occasions neutralized by the resistance of the walls of the capitals. The council and citizens of Carthage were not at all to be compared to the senate and people of Rome; the peril of Carthage after the first campaign of Regulus was infinitely more urgent than that of Rome after the battle of Cannae; yet Carthage had made a stand and been completely victorious. With what colour could it be expected that Rome would now deliver her keys to the victor, or even accept an equitable peace? Instead therefore of sacrificing practicable and important successes for the sake of such empty demonstrations, or losing time in the besieging of the two thousand Roman fugitives enclosed within the walls of Canusium, Hannibal had immediately proceeded to Capua before the Romans could throw in a garrison, and by his advance had induced this second city of Italy after long hesitation to join him. He might hope that, in possession of Capua, he would be able to seize one of the Campanian ports, where he might disembark the reinforcements which his great victories had wrung from the opposition at home.
When the Romans learned whither Hannibal had gone, they also left Apulia, where only a weak division was retained, and collected their remaining forces on the right bank of the Volturnus. With the two legions saved from Cannae Marcus Marcellus marched to Teanum Sidicinum, where he was joined by such troops as were at the moment disposable from Rome and Ostia, and advanced - while the dictator Marcus Junius slowly followed with the main army which had been hastily formed - as far as the Volturnus at Casilinum, with a view if possible to save Capua. That city he found already in the power of the enemy; but on the other hand the attempts of the enemy on Neapolis had been thwarted by the courageous resistance of the citizens, and the Romans were still in good time to throw a garrison into that important port. With equal fidelity the two other large coast towns, Cumae and Nuceria, adhered to Rome. In Nola the struggle between the popular and senatorial parties as to whether they should attach themselves to the Carthaginians or to the Romans, was still undecided. Informed that the former were gaining the superiority, Marcellus crossed the river at Caiatia, and marching along the heights of Suessula so as to evade the enemy's army, he reached Nola in sufficient time to hold it against the foes without and within.
In a sally he even repulsed Hannibal in person with considerable loss; a success which, as the first defeat sustained by Hannibal, was of far more importance from its moral effect than from its material results. In Campania indeed, Nuceria, Acerrae, and, after an obstinate siege prolonged into the following year (539), Casilinum also, the key of the Volturnus, were conquered by Hannibal, and the severest punishments were inflicted on the senates of these towns which had adhered to Rome. But terror is a bad weapon of proselytism; the Romans succeeded, with comparatively trifling loss, in surmounting the perilous moment of their first weakness. The war in Campania came to a standstill; then winter came on, and Hannibal took up his quarters in Capua, the luxury of which was by no means fraught with benefit to his troops who for three years had not been under a roof. In the next year (539) the war acquired another aspect. The tried general Marcus Marcellus, Tiberius Sempronius Gracchus who had distinguished himself in the campaign of the previous year as master of the horse to the dictator, and the veteran Quintus Fabius Maximus, took - Marcellus as proconsul, the two others as consuls - the command of the three Roman armies which were destined to surround Capua and Hannibal; Marcellus resting on Nola and Suessula, Maximus taking a position on the right bank of the Volturnus near Cales, and Gracchus on the coast near Liternum, covering Neapolis and Cumae. The Campanians, who marched to Hamae three miles from Cumae with a view to surprise the Cumaeans, were thoroughly defeated by Gracchus; Hannibal, who had appeared before Cumae to wipe out the stain, was himself worsted in a combat, and when the pitched battle offered by him was declined, retreated in ill humour to Capua. While the Romans in Campania thus not only maintained what they possessed, but also recovered Compulteria and other smaller places, loud complaints were heard from the eastern allies of Hannibal. A Roman army under the praetor Marcus Valerius had taken position at Luceria, partly that it might, in connection with the Roman fleet, watch the east coast and the movements of the Macedonians; partly that it might, in connection with the army of Nola, levy contributions on the revolted Samnites, Lucanians, and Hirpini. To give relief to these, Hannibal turned first against his most active opponent, Marcus Marcellus; but the latter achieved under the walls of Nola no inconsiderable victory over the Phoenician army, and it was obliged to depart, without having cleared off the stain, from Campania for Arpi, in order at length to check the progress of the enemy's army in Apulia. Tiberius Gracchus followed it with his corps, while the two other Roman armies in Campania made arrangements to proceed next spring to the attack of Capua.
The clear vision of Hannibal had not been dazzled by his victories. It became every day more evident that he was not thus gaining his object Those rapid marches, that adventurous shifting of the war to and fro, to which Hannibal was mainly indebted for his successes, were at an end; the enemy had become wiser; further enterprises were rendered almost impossible by the inevitable necessity of defending what had been gained. The offensive was not to be thought of; the defensive was difficult, and threatened every year to become more so. He could not conceal from himself that the second half of his great task, the subjugation of the Latins and the conquest of Rome, could not be accomplished with his own forces and those of his Italian allies alone. Its accomplishment depended on the council at Carthage, on the head-quarters at Cartagena, on the courts of Pella and of Syracuse. If all the energies of Africa, Spain, Sicily, and Macedonia should now be exerted in common against the common enemy; if Lower Italy should become the great rendezvous for the armies and fleets of the west, south, and east; he might hope successfully to finish what the vanguard under his leadership had so brilliantly begun. The most natural and easy course would have been to send to him adequate support from home; and the Carthaginian state, which had remained almost untouched by the war and had been brought from deep decline so near to complete victory by a small band of resolute patriots acting of their own accord and at their own risk, could beyond doubt have done this. That it would have been possible for a Phoenician fleet of any desired strength to effect a landing at Locri or Croton, especially as long as the port of Syracuse remained open to the Carthaginians and the fleet at Brundisium was kept in check by Macedonia, is shown by the unopposed disembarkation at Locri of 4000 Africans, whom Bomilcar about this time brought over from Carthage to Hannibal, and still more by Hannibal's undisturbed embarkation, when all had been already lost. But after the first impression of the victory of Cannae had died away, the peace party in Carthage, which was at all times ready to purchase the downfall of its political opponents at the expense of its country, and which found faithful allies in the shortsightedness and indolence of the citizens, refused the entreaties of the general for more decided support with the half-simple, half-malicious reply, that he in fact needed no help inasmuch as he was really victor; and thus contributed not much less than the Roman senate to save Rome. Hannibal, reared in the camp and a stranger to the machinery of civic factions, found no popular leader on whose support he could rely, such as his father had found in Hasdrubal; and he was obliged to seek abroad the means of saving his native country - means which itself possessed in rich abundance at home.