Its external relations were not in so favourable a position.  The nature of the case required that Macedonia should now take up the plans of Hannibal and Antiochus, and should try to place herself at the head of a coalition of all oppressed states against the supremacy of Rome; and certainly threads of intrigue ramified in all directions from the court of Pydna.  But their success was slight.  It was indeed asserted that the allegiance of the Italians was wavering; but neither friend nor foe could fail to see that an immediate resumption of the Samnite wars was not at all probable.  The nocturnal conferences likewise between Macedonian deputies and the Carthaginian senate, which Massinissa denounced at Rome, could occasion no alarm to serious and sagacious men, even if they were not, as is very possible, an utter fiction.  The Macedonian court sought to attach the kings of Syria and Bithynia to its interests by intermarriages; but nothing further came of it, except that the immortal simplicity of the diplomacy which seeks to gain political ends by matrimonial means once more exposed itself to derision.  Eumenes, whom it would have been ridiculous to attempt to gain, the agents of Perseus would have gladly put out of the way:  he was to have been murdered at Delphi on his way homeward from Rome, where he had been active against Macedonia; but the pretty project miscarried.

Bastarnae
Genthius

Of greater moment were the efforts made to stir up the northern barbarians and the Hellenes to rebellion against Rome.  Philip had conceived the project of crushing the old enemies of Macedonia, the Dardani in what is now Servia, by means of another still more barbarous horde of Germanic descent brought from the left bank of the Danube, the Bastarnae, and of then marching in person with these and with the whole avalanche of peoples thus set in motion by the land-route to Italy and invading Lombardy, the Alpine passes leading to which he had already sent spies to reconnoitre—­a grand project, worthy of Hannibal, and doubtless immediately suggested by Hannibal’s passage of the Alps.  It is more than probable that this gave occasion to the founding of the Roman fortress of Aquileia,(2) which was formed towards the end of the reign of Philip (573), and did not harmonize with the system followed elsewhere by the Romans in the establishment of fortresses in Italy.  The plan, however, was thwarted by the desperate resistance of the Dardani and of the adjoining tribes concerned; the Bastarnae were obliged to retreat, and the whole horde were drowned in returning home by the giving way of the ice on the Danube.  The king now sought at least to extend his clientship among the chieftains of the Illyrian land, the modern Dalmatia and northern Albania.  One of these who faithfully adhered to Rome, Arthetaurus, perished, not without the cognizance of Perseus, by the hand of an assassin.  The most considerable of the whole, Genthius the son and heir of Pleuratus, was, like his father, nominally in alliance with Rome; but the ambassadors of Issa, a Greek town on one of the Dalmatian islands, informed the senate, that Perseus had a secret understanding with the young, weak, and drunken prince, and that the envoys of Genthius served as spies for Perseus in Rome.