But, though Perseus stood almost alone, he was no contemptible antagonist. His army numbered 43,000 men; of these 21,000 were phalangites, and 4000 Macedonian and Thracian cavalry; the rest were chiefly mercenaries. The whole force of the Romans in Greece amounted to between 30,000 and 40,000 Italian troops, besides more than 10,000 men belonging to Numidian, Ligurian, Greek, Cretan, and especially Pergamene contingents. To these was added the fleet, which numbered only 40 decked vessels, as there was no fleet of the enemy to oppose it - Perseus, who had been prohibited from building ships of war by the treaty with Rome, was only now erecting docks at Thessalonica - but it had on board 10,000 troops, as it was destined chiefly to co-operate in sieges. The fleet was commanded by Gaius Lucretius, the land army by the consul Publius Licinius Crassus.
The consul left a strong division in Illyria to harass Macedonia from the west, while with the main force he started, as usual, from Apollonia for Thessaly. Perseus did not think of disturbing their arduous march, but contented himself with advancing into Perrhaebia and occupying the nearest fortresses. He awaited the enemy at Ossa, and not far from Larisa the first conflict took place between the cavalry and light troops on both sides. The Romans were decidedly beaten. Cotys with the Thracian horse had defeated and broken the Italian, and Perseus with his Macedonian horse the Greek, cavalry; the Romans had 2000 foot and 200 horsemen killed, and 600 horsemen made prisoners, and had to deem themselves fortunate in being allowed to cross the Peneius without hindrance. Perseus employed the victory to ask peace on the same terms which Philip had obtained: he was ready even to pay the same sum. The Romans refused his request: they never concluded peace after a defeat, and in this case the conclusion of peace would certainly have involved as a consequence the loss of Greece.
The wretched Roman commander, however, knew not how or where to attack; the army marched to and fro in Thessaly, without accomplishing anything of importance. Perseus might have assumed the offensive; he saw that the Romans were badly led and dilatory; the news had passed like wildfire through Greece, that the Greek army had been brilliantly victorious in the first engagement; a second victory might lead to a general rising of the patriot party, and, by commencing a guerilla warfare, might produce incalculable results. But Perseus, while a good soldier, was not a general like his father; he had made his preparations for a defensive war, and, when things took a different turn, he felt himself as it were paralyzed. He made an unimportant success, which the Romans obtained in a second cavalry combai near Phalanna, a pretext for reverting, as is the habit of narrow and obstinate minds, to his first plan and evacuating Thessaly. This was of course equivalent to renouncing all idea of a Hellenic insurrection: what might have been attained by a different course was shown by the fact that, notwithstanding what had occurred, the Epirots changed sides. Thenceforth nothing serious was accomplished on either side. Perseus subdued king Genthius, chastised the Dardani, and, by means of Cotys, expelled from Thrace the Thracians friendly to Rome and the Pergamene troops. On the other hand the western Roman army took some Illyrian towns, and the consul busied himself in clearing Thessaly of the Macedonian garrisons and making sure of the turbulent Aetolians and Acarnanians by occupying Ambracia. But the heroic courage of the Romans was most severely felt by the unfortunate Boeotian towns which took part with Perseus; the inhabitants as well of Thisbae, which surrendered without resistance as soon as the Roman admiral Gaius Lucretius appeared before the city, as of Haliartus, which closed its gates against him and had to be taken by storm, were sold by him into slavery; Corcnea was treated in the same manner by the consul Crassus in spite even of its capitulation. Never had a Roman army exhibited such wretched discipline as the force under these commanders. They had so disorganized the army that, even in the next campaign of 584, the new consul Aulus Hostilius could not think of undertaking anything serious, especially as the new admiral Lucius Hortensius showed himself to be as incapable and unprincipled as his predecessor. The fleet visited the towns on the Thracian coast without result. The western army under Appius Claudius, whose headquarters were at Lychnidus in the territory of the Dassaretae, sustained one defeat after another: after an expedition to Macedonia had been utterly unsuccessful, the king in turn towards the beginning of winter assumed the aggressive with the troops which were no longer needed on the south frontier in consequence of the deep snow blocking up all the passes, took from Appius numerous townships and a multitude of prisoners, and entered into connections with king Genthius; he was able in fact to attempt an invasion of Aetolia, while Appius allowed himself to be once more defeated in Epirus by the garrison of a fortress which he had vainly besieged. The Roman main army made two attempts to penetrate into Macedonia: first, ovei the Cambunian mountains, and then through the Thessalian passes; but they were negligently planned, and both were repulsed by Perseus.
The consul employed himself chiefly in the reorganization of the army - a work which was above all things needful, but which required a sterner man and an officer of greater mark. Discharges and furloughs might be bought, and therefore the divisions were never up to their full numbers; the men were put into quarters in summer, and, as the officers plundered on a large, the common soldiers plundered on a small, scale. Friendly peoples were subjected to the most shameful suspicions: for instance, the blame of the disgraceful defeat at Larisa was imputed to the pretended treachery of the Aetolian cavalry, and, what was hitherto unprecedented, its officers were sent to be criminally tried at Rome; and the Molossians in Epirus were forced by false suspicions into actual revolt. The allied states had war-contributions imposed upon them as if they had been conquered, and if they appealed to the Roman senate, their citizens were executed or sold into slavery: this was done, for instance, at Abdera, and similar outrages were committed at Chalcis. The senate interfered very earnestly[4]: it enjoined the liberation of the unfortunate Coroneans and Abderites, and forbade the Roman magistrates to ask contributions from the allies without its leave. Gaius Lucretius was unanimously condemned by the burgesses. But such steps could not alter the fact, that the military result of these first two campaigns had been null, while the political result had been a foul stain on the Romans, whose extraordinary successes in the east were based in no small degree on their reputation for moral purity and solidity as compared with the scandals of Hellenic administration. Had Philip commanded instead of Perseus, the war would presumably have begun with the destruction of the Roman army and the defection of most of the Hellenes; but Rome was fortunate enough to be constantly outstripped in blunders by her antagonists. Perseus was content with entrenching himself in Macedonia - which towards the south and west is a true mountain-fortress - as in a beleaguered town.
4. The recently discovered decree of the senate of 9th Oct. 584, which regulates the legal relations of Thisbae (Ephemeris epigraphica, 1872, p. 278, fig.; Mitth. d. arch. Inst., in Athen, iv. 235, fig.), gives a clear insight into these relations.