Sellasia

A town in Laconia (southern Greece)

It lay about eight miles north of Sparta, overlooking the middle valley of the Oenus (Kelephina), a tributary of the Eurotas, and occupying a strategic position on the road leading up into Arcadia. Described by Diodorus as a city (polis), though it is unlikely to have possessed that formal status, Sellasia was plundered and burned by the Theban Epaminondas (370), but recaptured by the Spartans five years later.

In 222 it was the scene of one of the decisive battles of the Hellenistic age. In this engagement, the Macedonian monarch Antigonus III Doson confronted King Cleomenes III of Sparta, whose attempted employment of social revolution to serve Spartan expansion had caused great alarm. Although our three sources for the battle are conflicting, it is clear that Cleomenes occupied the river valley (which was suitable for phalanx warfare) and the hills on either side, but was nevertheless outflanked and succumbed to superior numbers and experience. His army was completely destroyed, and Antigonus entered Sparta unopposed. Sellasia itself suffered destruction and its population was reduced to slavery. Its site has not been identified with certainty; two hills, Ayios Konstantinos and the lower Paleogoulas, have been suggested.