Rome was not long left to the tranquil enjoyment of her victory. Peace had been concluded. Not the citizens of Rome alone, but all Italy, yearned for a lasting peace. And yet the Roman senate, in defiance of popular feeling, was constrained to embark promptly on the adventures of a new and perilous war or to be false to the whole tenor of its policy up to that time.
Rome’s success in dealing with Macedonia was due, as has already been stated, to the fact that she extended her protection to the smaller Greek states and thus gained a base from which she could hold the larger states of Greece, Macedonia first and foremost, in check. This policy obliged the Romans in the year 200 B.C. to go to the help of Egypt, which was hard pressed by the combined forces of Macedonia and Syria. Ever since the accession of the youthful Ptolemy Epiphanes in 205 B.C., Macedonia and Syria had united with a view to dividing the Egyptian empire and its dependencies between themselves.
Syria’s share was to be Egypt and Cyprus, Macedonia’s Cyrene, Ionia, and the islands of the Ægean Sea. Rome was the less able to be an indifferent spectator of the initial successes of these two great powers since they were won at the expense of the states of Pergamus, Rhodes, and Miletus, which were among her allies. In the case of Syria the Romans attained their object by the embassy of Marcus Æmilius Lepidus. Antiochus the Great evacuated Egypt. Philip, however, would not stay his hand, and thus the Macedonian War broke out, to be decided in favour of the Romans, after many years of indifferent success, by the advance of Flaminius into Thessaly and his victory at Cynoscephalæ (197 B.C.). At the Isthmian games Flaminius proclaimed that all Greeks were free, but the real effect of the proclamation was to reduce all Greek states to a common level of impotence and to give none of them any lasting satisfaction. The Ætolians, who had been the allies of Rome in the Macedonian War, and took no small credit to themselves for the result, were now the most bitterly enraged against her. Antiochus the Great, of Syria, profited by the prevailing sentiment to press forward in Asia Minor. Hannibal, who had been driven from Carthage, appeared at his court and endeavoured, though without success, to induce him to take the offensive against Italy. War was nevertheless inevitable. Antiochus had command of the sea, and crossed to Eubœa and Thessaly. The Ætolians rose in rebellion. The Romans, however, took up the quarrel with no lack of spirit. After the flower of Antiochus’ forces had been vanquished at Thermopylæ, and the Syrian fleet, under the command of Hannibal, had twice suffered defeat, the Scipios crossed over into Asia Minor and destroyed the main army of Syria at Magnesia. A sanguinary conflict ended in the conquest of the mountain cantons of Ætolia (191-189) and the subjugation of the Galatian hordes (188). Antiochus was forced to resign his pretensions to Asia Minor.