Phoenice had been previously taken by Illyrians acting under Queen Teuta, in 230 BC, after a Gaulish garrison of 800 men surrendered to the larger Illyrian force. In reaction, the Epirote League sent in an army to retake Phoenice. They took up positions at a river outside of Phoenice. Meanwhile, 5,000 Illyrians under Scerdilaidas had advanced inland into Epirus from Southern Illyria and reached a pass just outside Antigoneia. The Epirotes reacted by dividing their army, sending a small detachment to protect Antigoneia whilst keeping their main body outside of Phoenice. The Illyrians at Phoenice, seeing the Epirote army was divided, advanced towards their camp and crossed the river. The next day, the forces engaged each other in battle. The Greek forces were routed and badly defeated, with many being killed or captured, and the remnants of the army fled to Atinania.

Following the battle, the Epirote league had failed to take control of Phoenice, the most powerful city of Epirus. Scerdilaidas forces had also occupied areas of northern Epirus up until Antigoneia. The Epirotes requested assistance from the Aetolian and Achaean Leagues, with the former having been defeated previously by Illyrians under Agron at Medion in 232 BC. Both leagues sent a combined relief army to the Epirotes which arrived at Helicranum, nearby modern Ioannina, in 230 BC. The Illyrians at Phoenice and those outside Antigoneia under Scerdilaidas joined forces in Epirus and advanced towards Helicranum at the heart of Epirus, preparing to engage the new Greek force in battle. However, they were called back to Illyria by Teuta before the battle begun, following an Illyrian revolt in support of Dardania. The Dardanian ruler, Longarus, had invaded Illyria, sparking an insurrection. Thus, after briefly plundering the Epirote coast, the Illyrians made a truce with the Epirotes and retreated. They also gave up the freemen they had captured at the battle along with the city of Phoenice for a ransom. Afterwards, taking slaves and booty the Illyrians returned to Illyria by sea, whilst the 5,000 under Scerdilaidas retreated northwards to the pass of Antigoneia.

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Wikipedia