Cleomenean War
228 BCE.
Shown on the map at 37.350°, 22.352°.
The Cleomenean War (229/228–222 BC) was fought between Sparta and the Achaean League for the control of the Peloponnese. Under the leadership of king Cleomenes III, Sparta initially had the upper hand, which forced the Achaean League to call for help the Macedonian king Antigonos Doson, who decisively defeated Cleomenes in the battle of Sellasia in 222. In 235 BC, Cleomenes III (r. 235–222 BC) ascended the throne of Sparta and began a program of reform aimed at restoring traditional Spartan discipline while weakening the influence of the ephors, elected officials who, though sworn to uphold the rule of Sparta's kings, had by the time of Cleomenes come to wield extraordinary political power in the Spartan system. When, in 229 BC, the ephors sent Cleomenes to seize a town on the border with Megalopolis, the Achaeans declared war. Cleomenes responded by ravaging Achaea. At Mount Lycaeum he defeated an army under Aratus of Sicyon, the strategos of the Achaean League, that had been sent to attack Elis, and then routed a second army near Megalopolis. In quick succession, Cleomenes cleared the cities of Arcadia of their Achaean garrisons, before crushing another Achaean force at Dyme.
Text from the Wikipedia article Cleomenean War, licensed CC BY-SA 4.0.