Today's Passage
This passage marks the dramatic opening of actual hostilities in the Peloponnesian War with the Theban attack on Plataea in 431 BCE.
Crawley Translation (1910)
Beginning of the Peloponnesian War—First Invasion of Attica—Funeral Oration of Pericles
The war between the Athenians and Peloponnesians and the allies on either side now really begins. For now all intercourse except through the medium of heralds ceased, and hostilities were commenced and prosecuted without intermission. The history follows the chronological order of events by summers and winters.
The thirty years’ truce which was entered into after the conquest of Euboea lasted fourteen years. In the fifteenth, in the forty-eighth year of the priestess-ship of Chrysis at Argos, in the ephorate of Aenesias at Sparta, in the last month but two of the archonship of Pythodorus at Athens, and six months after the battle of Potidæa, just at the beginning of spring, a Theban force a little over three hundred strong, under the command of their Boeotarchs, Pythangelus, son of Phyleides, and Diemporus, son of Onetorides, about the first watch of the night, made an armed entry into Plataea, a town of Boeotia in alliance with Athens. The gates were opened to them by a Plataean called Naucleides, who, with his party, had invited them in, meaning to put to death the citizens of the opposite party, bring over the city to Thebes, and thus obtain power for themselves. This was arranged through Eurymachus, son of Leontiades, a person of great influence at Thebes. For Plataea had always been at variance with Thebes; and the latter, foreseeing that war was at hand, wished to surprise her old enemy in time of peace, before hostilities had actually broken out. Indeed this was how they got in so easily without being observed, as no guard had been posted. After the soldiers had grounded arms in the market-place, those who had invited them in wished them to set to work at once and go to their enemies’ houses. This, however, the Thebans refused to do, but determined to make a conciliatory proclamation, and if possible to come to a friendly understanding with the citizens. Their herald accordingly invited any who wished to resume their old place in the confederacy of their countrymen to ground arms with them, for they thought that in this way the city would readily join them.
Modern Translation
The Peloponnesian War between Athens and Sparta, along with their respective allies, now truly commenced. From this point forward, all diplomatic communication ceased except through official heralds, and military operations continued without pause. This historical account follows events in chronological sequence, organized by summers and winters.
The Thirty Years' Peace, established following Athens' subjugation of Euboea, endured for fourteen years. In the fifteenth year—during the forty-eighth year of Chrysis's tenure as priestess at Argos, under Aenesias's ephorate in Sparta, and in the tenth month of Pythodorus's archonship at Athens—six months after the Battle of Potidaea and just as spring began, a Theban force of slightly more than three hundred men launched a surprise attack on Plataea. Led by their commanders Pythangelus (son of Phyleides) and Diemporus (son of Onetorides), they entered the Boeotian city—an ally of Athens—during the first watch of the night.
Their entry was facilitated by Naucleides, a Plataean traitor who, along with his faction, had invited them in. His plan was to eliminate his political opponents, deliver the city to Theban control, and thereby secure power for his group. This conspiracy was orchestrated through Eurymachus, son of Leontiades, a prominent Theban figure. Plataea had long been hostile to Thebes, and the Thebans, anticipating the coming war, sought to capture their traditional enemy during peacetime, before hostilities officially began. This explains their easy, undetected entry—no sentries had been posted.
After the soldiers assembled in the marketplace, the conspirators urged immediate action against their opponents' homes. The Thebans, however, declined this approach. Instead, they opted for diplomacy, hoping to win over the citizenry peacefully. Their herald proclaimed that anyone wishing to rejoin the ancestral Boeotian confederation should lay down their arms alongside the Thebans, believing this strategy would persuade the city to join them willingly.
Historical Context
This passage marks the dramatic opening of actual hostilities in the Peloponnesian War with the Theban attack on Plataea in 431 BCE. Plataea, though ethnically Boeotian, was a long-standing Athenian ally dating back to their joint victory over Persia at the Battle of Plataea in 479 BCE. The nighttime assault represents Thebes' attempt to secure a strategic advantage before war was formally declared. The attack failed when the Plataeans rallied, killed or captured the Theban force, and executed the prisoners despite promises of safety. This violation of Greek customs regarding prisoners provided Athens with moral justification for war. The incident demonstrates how local conflicts between neighbors (Thebes-Plataea) became entangled with the larger struggle between Athens and Sparta, ultimately triggering the devastating conflict that would consume Greece for nearly three decades.
Key Themes
Annotations & References
Greek Chronology
Thucydides uses a triple-dating system referencing the priestess of Hera at Argos, Spartan ephors, and Athenian archons. This reflects the absence of a unified calendar in ancient Greece and Thucydides' attempt to establish precise chronology for his historical method.
Learn more →Plataea's Strategic Importance
Plataea controlled routes between Attica and Boeotia. Its alliance with Athens dated to 519 BCE and was cemented at the Battle of Plataea (479 BCE). The city's location made it a perpetual flashpoint between Athens and Thebes.
Learn more →Boeotarchs
The Boeotarchs were the chief magistrates of the Boeotian League, typically seven in number. They commanded federal troops and represented the confederation's military and political authority, demonstrating this attack's official nature.
Learn more →Greek Concepts of War and Peace
The Theban attack violated Greek customs by occurring during peacetime and at night. Such violations of traditional warfare norms would become increasingly common during the Peloponnesian War, reflecting the conflict's totalizing nature.
Learn more →Parallel Ancient Sources
Herodotus: Histories (Book 6.108)
Describes the origin of the Plataea-Athens alliance when Plataea sought Athenian protection against Theban aggression, establishing the historical enmity that culminates in this attack.
Read passage →Plutarch: Life of Pericles (Chapter 17)
Provides context for Pericles' strategy at the war's outbreak and Athens' response to early provocations, including the significance of the Plataea incident in justifying Athenian policy.
Read passage →Xenophon: Hellenica (Book 3.5.3-5)
Describes a similar nighttime betrayal of a city during the Corinthian War, showing how such tactics became normalized in Greek warfare following the precedents set during the Peloponnesian War.
Read passage →Discussion Questions
- How does the Theban decision to attempt persuasion rather than immediate violence reflect Greek political culture and the tension between force and diplomacy?
- What does the role of internal betrayal (stasis) in this episode suggest about the nature of Greek city-state politics during this period?
- How might the attack's timing—at night, during peacetime—have affected contemporary Greek perceptions of the war's legitimacy?
- In what ways does Thucydides' precise dating system reflect his historical methodology and his intended audience?