Megarian Decree

The Megarian Decree was a set of economic sanctions levied upon Megara c. 432 BC by the Athenian Empire shortly before the outbreak of the Peloponnesian War.

[1] The decree addressed the Megarians' supposed trespass on land sacred to Demeter known as the Hiera Orgas,[2] the killing of the Athenian herald who was sent to their city to reproach them, and giving shelter to slaves who had fled from Athens.

[3] The Megarian decree effectively blocked Megara from trading in any port within the Delian League, isolating the city and greatly damaging its economy.

The exact influence the Megarian Decree had on the beginning of the Peloponnesian War is a matter that is highly debated to this day.

His play The Acharnians (II.530-7) mentions how the decree left the Megarians "slowly starving" and caused them to appeal to the Spartans for aid.

[11] However, Thucydides also reports that the Spartans had sought a declaration of war from the Peloponnesian League during the rebellion of Samos in 440, well before the Megarian decree had been passed.

Donald Kagan interprets the decree as an attempt by Athens to solve a problem without breaking the Thirty Years' Peace with Sparta.

At the beginning of the Second Peloponnesian War, the Athenians invaded Megara twice a year with large forces to ravage their land and maintained a naval blockade.