Philip V of Macedon () faced immediate challenges to his authority by the Illyrian Dardani and Aetolian League. PhilipV and his allies were successful against the Aetolians and their allies in the Social War (220–217 BC), yet he made peace with the Aetolians once he heard of incursions by the Dardani in the north and the Carthaginian victory over the Romans at the Battle of Lake Trasimene in 217BC. Demetrius of Pharos is alleged to have convinced PhilipV to first secure Illyria in advance of an invasion of the Italian peninsula. In 216BC, PhilipV sent a hundred light warships into the Adriatic Sea to attack Illyria, a move that prompted Scerdilaidas of the Ardiaean Kingdom to appeal to the Romans for aid. Rome responded by sending ten heavy quinqueremes from Roman Sicily to patrol the Illyrian coasts, causing PhilipV to reverse course and order his fleet to retreat, averting open conflict for the time being.