The island of Naxos wishes to secede from the Delian League, but is blockaded by Athens and forced to surrender. Naxos becomes a tribute-paying member of the Delian League. This action is considered high-handed and resented by the other Greek city states.
Cimon carries the war against Persia into Asia Minor and wins the Battle of the Eurymedon in Pamphylia. This is a decisive defeat of the Persians as Cimon's land and sea forces capture the Persian camp and destroy or capture the entire Persian fleet of 200 triremes (manned by Phoenicians). Many new allies of Athens are now recruited, such as the trading city of Phaselis on the Lycian-Pamphylian border.
King Xerxes I of the Persian Empire,[2] together with his eldest son, is murdered by one of his Ministers, Artabanus the Hyrcanian. The Persian general, Megabyzus, is thought to have been one of the conspirators in the assassination.
Artabanus gains control of the Achaemenid state for several months. However, he is betrayed by Megabyzus and is killed by Xerxes' son, Artaxerxes.
Thasos revolts from the Delian League. The revolt arises from rivalry over trade with the Thracian hinterland and, in particular, over the ownership of a gold mine. Athens under Kimon lays siege to Thasos after the Athenian fleet defeats the Thasos fleet
When the Messenian helots (serfs) revolt against their Spartan masters following the severe earthquake, King Archidamus II organises the defence of Sparta. The helots fortify themselves at Mount Ithome.
Egypt seizes the opportunity created by the murder of Xerxes I to revolt against Persia. The revolt is led by Inaros, a Libyan, who gains control of the Delta region and is aided by the Athenians.
Artaxerxes I succeeds Xerxes as king of the Persian empire.
In Athens, the democratic statesman Ephialtes and the young Pericles attempt to get the oligarchic Kimonostracized for allegedly receiving bribes. Kimon is charged by Pericles and other democratic politicians with having been bribed not to attack the King of Macedonia (who may have been suspected of covertly helping the Thasian rebels). Though Kimon is acquitted, his influence on the Athenian people is waning.
Themistocles, who is in exile, approaches the Persian King Artaxerxes I seeking Persian help in regaining power in Athens. Artaxerxes is unwilling to help him, but gives him the satrapy of Magnesia.
After a two year siege, Thasos falls to the Athenians under Kimon who compels the Thasians to destroy their walls, surrender their ships, pay an indemnity and an annual contribution to Athens.
The Spartans try to conquer the mountain stronghold of Mt Ithome in Messenia, where a large force of rebellious helots have taken refuge. They ask their allies from the Persian Wars, including the Athenians, to help.
Kimon seeks the support of Athens' citizens providing help to Sparta. Although Ephialtes maintains that Sparta is Athens' rival for power and should be left to fend for itself, Kimon's view prevails. Kimon then leads 4,000 hoplites to Mount Ithome.
After an attempt to storm Mt. Ithome fails, the Spartans start to distrust the Athenians over concerns that they may take the side of the helots. Retaining their other allies, the Spartans sent Kimon and his men home. This insulting rebuff causes the collapse of Kimon's popularity at Athens. Outrage over the dismissal swings Athenian opinion towards Ephialtes' views.
Ephialtes passes a law in the Athenian ecclesia, which reforms the Areopagus, limiting its power to judging cases of homicide and religious crimes. He considers the Areopagus to be the centre of conservatism and Ephialtes' victory is seen as a defeat for the conservatives and the members of the oligarchy.
Argos, taking advantage of Spartan preoccupation with the revolt of its helots, finally conquers Mycenae. The inhabitants of the town are dispersed, with some finding their way into Macedonia.
Ephialtes, with the support of Pericles, reduces the power of the Athenian Council of Areopagus (filled with ex-archons and so a stronghold of oligarchy) and transfers them to the people, i.e. the Council of Five Hundred, the Assembly and the popular law courts. The office of Judge is made a paid position and is recruited by lot from a list to which every citizen can have his name added.
Egypt revolts against Persian rule. The Egyptian leader, Inaros, asks Athens for assistance, which is willingly provided as Athens has plans to trade with and colonise Egypt. A force of 200 Athenian triremes, which is campaigning in Cyprus, is immediately ordered to Egypt to render assistance.
Achaemenes, Persian satrap (governor) of Egypt, is defeated and slain in a battle at Papremis, on the banks of the Nile River, by Egyptian forces.
The First Peloponnesian War breaks out between the Delian League (led by Athens) and a Peloponnesian alliance (led by Sparta), caused in part by Athens' alliance with Megara and Argos and the subsequent reaction of Sparta. The Athenians have built long walls for the Megarans to their port at Nisaea, thereby earning the enmity of Megara's old rival Corinth.
Argos rises against Sparta. Athens supports Argos and Thessaly. The small force that is sent by Sparta to quell the uprising in Argos is defeated by a joint Athenian and Argos force at Oenoe. (Battle of Oenoe)
Ducetius, a Hellenised leader of the Siculi, an ancient people of Sicily, takes advantage of the confusion that follows the collapse of the tyranny in Syracuse and other Sicilian states. With the support of the Syracusan democracy, he drives out the colonists of the former tyrant Hieron from Catana and restores it to its original inhabitants.
The sculpture Apollo with battling Lapiths and centaurs is built on the west pediment of the Temple of Zeus in Olympia (approximate date). Only fragments remain and are today preserved at the Archaeological museum in Olympia.
A metope relief of Athena, Heracles and Atlas are made on a frieze in the Temple of Zeus in Olympia (approximate date). It is now preserved at the Archaeological museum in Olympia.
A statue of Apollo is cast (approximate date), of which today remains one leg, preserved at the Louvre, and the head, known as the Chatsworth Head, preserved at the British Museum.