The First Battle of Lamia was fought in 209 BC between the forces of Philip V of Macedon and the Aetolians led by Pyrrhias.

He invested and took Echinus, using extensive siege works, having beaten back an attempt to relieve the town by the Aetolian strategos Dorimachus and the Roman fleet, now commanded by the proconsul Publius Sulpicius Galba.

Sulpicius and Dorimachus took Aegina, an island in the Saronic Gulf, which the Aetolians sold to Attalus, the Pergamene king, for thirty talents, and which he was to use as his base of operations against Macedon in the Aegean Sea.

In the spring of 209 BC, Philip received requests for help from his ally the Achaean League in the Peloponnesus who were being attacked by Sparta and the Aetolians.

He also heard that Attalus had been elected one of the two supreme commanders of the Aetolian League, and rumours that he intended to crossover the Aegean from Asia Minor.