The regions of ancient Greece were sub-divisions of the Hellenic world as conceived by the Ancient Greeks of antiquity, shown by their presence in the works of ancient historians and geographers or in surviving legends and myths.

Acarnania is a region of west-central Greece that lies along the Ionian Sea, west of Aetolia, with the Achelous River for a boundary, and north of the gulf of Calydon, which is the entrance to the Gulf of Corinth. Today it forms the western part of the regional unit of Aetolia-Acarnania. The capital and principal city in ancient times was Stratos. The north side of Acarnania of the Corinthian Gulf was considered part of the region of Epirus.