History of the Peloponnesian War

They also sent for Demosthenes, who had led the army of the Athenians into Aetolia, to come and be their leader, as well as for the twenty Athenian ships[*](After the return of the thirty ships (3.98.5), these twenty had been sent out again round the Peloponnesus. Their real goal was Naupactus (3.114.2), but answering the appeal of the Acarnanians they turned aside for the moment to the Ambracian Gulf (3.107.1).) which happened to be off the coast of Peloponnesus under the command of Aristotle son of Timocrates and Hierophon son of Antimnestus.

A messenger was also sent by the Ambraciots at Olpae to the city of Ambracia with a request that all the forces of the town should be dispatched to their aid, for they feared that Eurylochus and his troops might not be able to make their way through the Acarnanians, and, in that case, that they themselves would either have to fight single-handed, or, if they wished to retreat, would find that unsafe.

Now the Peloponnesian forces under Eurylochus, when they learned that the Ambraciots had arrived at Olpae, set out from Proschium with all speed to reinforce them, and crossing the Acheloiis advanced through Acarnania, which was without defenders because of the reinforcements which had been sent to Argos, and as they advanced they had the city of Stratus with its garrison on their right, and the rest of Acarnania on their left.