The Carthaginians also sought to embarrass Rome in Sardinia and Macedon. In 215 a force was despatched under Hasdrubal the Bald to Sardinia, where the natives were already restive under Roman rule, especially as the governor was ill. Rome energetically sent out a legion under T. Manlius Torquatus, who knew the island well. Landing at Cagliari he defeated the rebels before the arrival of Hasdrubal, who had been delayed by a storm. He then forced Hasdrubal’s army to fight and won a decisive victory. Thus the Carthaginian attempt miscarried, and they made no further efforts to regain the island.
The extension of the war to Greece, known as the First Macedonian War, was little more than a side-show. Its ramifications belong rather to the history of the Greek world and its importance derives largely from the fact that it drew Rome closer to that world. For if Hannibal hoped that it would seriously distract Rome’s attention, he miscalculated. Philip of Macedon, long suspicious of Rome’s intervention in Illyria, was watching Hannibal’s progress in Italy with keen self-interest. When he received news of Trasimene, he hastily terminated the war he was waging in Greece so as to have his hands free; at Naupactus he concluded a peace with the Aetolians, many of whom viewed with apprehension ‘the cloud rising in the west’. Driven on by dreams of conquest and by the advice of the pirate chief Demetrius, he built a fleet of light cutters which he launched in the Adriatic in 216 in order to obtain a naval base there and to reinstate Demetrius at Pharos. The approach of a Roman fleet caused his hasty withdrawal; but he had shown his hand. When it was clear that Cannae would not end the war Philip took the decisive step of forming an alliance with Hannibal; it was to be offensive during the war and defensive afterwards, when Hannibal would deal with Italy while Philip and Demetrius could assert their claims to Rome’s Illyrian possessions and Corcyra.15
News of the alliance reached Rome through the capture of Philip’s envoys and despatches. To meet the new danger on her flank, she ordered M. Valerius Laevinus, a praetor in command at Tarentum, to watch Philip and if necessary to cross to Illyria with 50 warships. In 214 Philip attacked the naval bases of Illyria, but Laevinus quickly recaptured Oricus, relieved Apollonia, forced Philip to burn his boats and retire to Macedon, and established himself on the Illyrian coast. Philip could only hope to dislodge him with the help of the Carthaginian fleet, for which he waited in vain, though he regained access to the Adriatic by capturing Lissus (213?). Laevinus, who feared the possible advent of a Carthaginian fleet, turned to a diplomatic offensive against Philip by stirring up war against him in Greece. In 211 he concluded an alliance with the Aetolians: they were to operate by land and keep any territory wrested from Philip; Rome was to supply naval help and have the portable booty or part of it.16 The alliance – the first concluded between Rome and a Greek people – was soon joined by many Greek states, Elis, Messenia and Sparta, by Attalus of Pergamum and by the chieftains of Thrace and Illyria. Not only was all possibility of Philip helping Hannibal in Italy averted, but by this skilful move the war in Greece was shifted largely on to the shoulders of the Greeks themselves.
In four campaigns Philip hurried with surprising energy from front to front (211–208). In 211 or 210 Laevinus was succeeded by P. Sulpicius Galba who celebrated his arrival in the Aegean by failing to relieve Echinus which Philip was besieging, although he captured Aegina. So the war dragged on, notwithstanding fruitless attempts by various parties to negotiate a peace. Throughout this war Philip in vain awaited naval help from Carthage and the growing realization at Rome that this support to their enemy was not forthcoming led to a gradual slackening of interest in this theatre of war. In 208 Attalus returned to Asia, and Rome did little in Greece; the Aetolians could be left to oppose Philip by themselves. This might suit Rome, but it did not suit the Aetolians, who ended the Hellenic War in 206 by making peace with Philip. This act, which Rome herself had made inevitable, at last stirred her to activity. In 205 P. Sempronius Tuditanus was sent out with a large force to succeed Sulpicius and to protect Illyria. But a successful demonstration there was not sufficient to rekindle the spirit of Aetolia against Philip. So Rome decided to abandon the war; she did not wish for a long single-handed struggle with Philip, especially at a time when, as will be seen, she was preparing to make her final effort against Carthage. Sempronius was ordered to decline battle and to come to terms. The Peace of Phoenice (205), which was concluded on the basis of uti possidetis, made only slight territorial adjustments. It was clearly an agreement for the mutual convenience of Rome and Philip. The Romans had been drawn into Greek affairs to meet a specific danger; with that removed they were ready to leave Greece to work out its own salvation. For Philip further resistance was futile, since no support came from Carthage. Further, the eastern world, of which Rome knew so little but was soon to learn so much, claimed his thoughts. Thus Carthage had signally failed to utilize her ally in Greece to the full in her struggle with Rome.