The reasons for Rome's intervention in Greece from the 3rd century BC are many: a call for help from the cities of Illyria; the fight against Philip V of Macedon, whose naval policy troubled Rome and who had been an ally of Hannibal’s; or assistance to Macedon’s adversaries in the region (Pergamon, Rhodes and the Achaean League). After his victory at Battle of Cynoscephalae, Flaminius proclaimed the “liberation” of Greece. Neither were commercial interests absent as a factor in Rome's involvement. Delos became a free port under the Roman Republic's protection in 167 BC. Thus Italian merchants grew wealthier, more or less at the expense of Rhodes and Corinth (finally destroyed the same year as Carthage in 146 BC). The political system of the Greek city, on the continent and on the islands, was maintained, indeed developed, during the first centuries of the Roman Empire.