243 BC

By place

Egypt

• Ptolemy III returns from Syria due to a revolt in Egypt. As a result, Seleucus II is able to regain control of his kingdom with the Egyptians being pushed out of Mesopotamia and part of Northern Syria.
• Ptolemy III returns from his conquests of Seleucid territory with a large amount of treasure and works of art, including many statues of Egyptian gods carried off to Persia by Cambyses. He restores the statues to the Egyptian temples and earns the title of Euergetes.

  Greece

• Without a declaration of hostilities, Greek statesman, Aratus of Sicyon, who has gradually built up the Achaean League into a major power in Greece, makes a surprise attack on Corinth and forces the withdrawal of the Macedonian occupation troops. Megara, Troezen, and Epidaurus also desert the Macedonian King Antigonus II.
• Drawing upon the tradition of the Spartan lawgiver, Lycurgus, the young Eurypontid king of Sparta, Agis IV, seeks to reform a system that distributes the land and wealth unequally and burden the poor with debt. He proposes the cancellation of debts and the division of the Spartan homeland into separate lots for each of its citizens. Full citizenship is to be extended to many perioeci and foreigners. In addition to pursuing these reforms, Agis seeks the restoration of the Lycurgan system of military training. Agis is supported by his wealthy mother and grandmother, by his uncle Agesilaus, and by Lysander, who is an ephor.