Megaris
Hybla Megala founded by settlers from Megara
Herakleia Pontika founded by colonists from Megara and named after Herakles, who it was believed entered the underworld through a nearby cave.
August 7
The philosopher Euclid is born in Megara.
A democratic uprising occurs in Megara.
Death of Euclid, who had founded the Megarian school of philosophy, in Megara.
Antigonos II blockades Athens and destroys a temple to Poseidon between it and Megara. Ptolemy II sends a fleet to break the blockade.
Megara expels is Macedonian garrison and joins the Achaian League.
Megara leaves the Achaian League and joins the Boeotian League.
Megara, besieged by the Romans under Quintus Fufius Calenus, attempt to unleash lions on the Romans. The lions instead attack unarmed Megarians.