All 26 chapters, by book and phase — from the Archaeology to the oligarchic coup of 411.
The 26 chapters follow Thucydides's own structure: eight books, each covering one or more years of the war. Books I–II lay the foundations and deliver the plague. Books III–V trace the inconclusive middle war. Books VI–VII are the Sicilian disaster. Book 8 is the unfinished aftermath. Read in order — the weight of the History depends on accumulation.
The Archaeology, the Pentecontaetia, and the debates that made war inevitable.
Thucydides opens by claiming superiority over all earlier historians, then proves it by methodically demolishing Greek mythology through material evidence and inference.
A minor colonial civil war at Epidamnus cascades through Corinthian pride and Corcyraean appeals to Athens into the chain of grievances that makes war between Athens and Sparta inevitable.
At Sparta's confederate congress, allied grievances against Athens produce two great opposing speeches — Corinthian urgency versus Athenian realism — before Sparta votes for war.
The Pentecontaetia compresses five decades of Athenian imperial growth into a surgical narrative that gives the Spartan fear of Athens its full historical basis.
Sparta's pre-war ultimatums are diplomatically ingenious and designed to be refused; Pericles's response to each makes explicit the strategic logic Athens will follow into the war.
Pericles's funeral oration, the Attic invasions, and the plague that killed him.
Pericles's Funeral Oration — democracy, open society, Athens as the school of Hellas — stands at the exact moment before plague and atrocity begin to test every claim it makes.
The plague of Athens — described by a survivor with clinical precision — kills Pericles, dissolves social order, and removes from the war the one mind capable of holding Athens to a winning strategy.
Phormio's audacious naval victories against superior Peloponnesian forces demonstrate the tactical advantage that Athenian naval discipline and seamanship provide — while Plataea endures its siege.
The Mytilenean Debate, Corcyra, Pylos, Brasidas in Thrace.
The Mytilenean Debate — Cleon for massacre, Diodotus against it — is resolved by one ship's rowing speed; the result is one of the History's sharpest arguments about terror, interest, and democratic decision-making.
The judicial murder of the Plataeans and the Corcyrean civil war's savagery give Thucydides the occasion for his most direct analysis of how war corrupts language, justice, and all inherited political norms.
Demosthenes's journey from disaster in Aetolia to brilliant irregular victory in Acarnania shows how military intelligence, once bought by catastrophe, can transform a commander's capacity.
The surrender of the Spartan force at Sphacteria — 292 men including 120 Spartiates — shocks the Greek world and hands Athens a strategic trump card that nearly ends the war on Athenian terms.
Sicily's Congress of Gela produces Hermocrates's first great speech on Sicilian unity; Corcyra's oligarchs are exterminated; Athens grasps at Megara and falls short.
Brasidas's northern campaign — politically deft, militarily brilliant — detaches Athens's Thracian empire and costs Thucydides the command that led to his exile and his opportunity to write the History.
The Peace of Nicias, the Argive alliance, and the Melian Dialogue.
The deaths of Cleon and Brasidas in a single battle outside Amphipolis remove the two war-drivers, producing the Peace of Nicias — a truce that solves nothing and satisfies nobody.
The battle of Mantinea — the war's largest hoplite engagement — restores Spartan military prestige after the Sphacteria humiliation and collapses the anti-Spartan coalition Alcibiades had built.
The Melian Dialogue — the ancient world's starkest statement of political realism, 'the strong do what they can and the weak suffer what they must' — is answered by the Sicilian disaster that follows immediately.
The expedition voted, launched, and destroyed.
The Sicilian vote, driven by Alcibiades's ambition and Nicias's backfired caution, and shadowed by the Hermae mutilation scandal, launches the expedition that will destroy Athens's best army.
Hermocrates warns Syracuse while Athens's generals disagree about strategy, and Alcibiades — recalled to face trial — defects to Sparta and begins advising Athens's enemies.
The Athenian investment of Syracuse almost succeeds before Gylippus's arrival through the one unblocked pass reverses the strategic situation permanently — one day's timing changes the war.
Gylippus reverses the siege's logic while Sparta's occupation of Decelea squeezes Athens from Attica itself; Nicias's honest letter to Athens is the History's most remarkable administrative document.
Demosthenes's night assault on Epipolae succeeds then catastrophically fails in the darkness; his immediate call to withdraw is overridden by Nicias's paralysis — sealing the expedition's fate.
The destruction of the Athenian expedition in Sicily — the naval battle in the Great Harbour, the overland retreat, the quarries — is the most carefully narrated catastrophe in classical historiography.
Oligarchic revolution, Persian intervention, and the recall of Alcibiades.
After Sicily, Athens recovers with remarkable resilience while Ionia revolts, Persia funds Spartan fleets, and the war enters its most complex diplomatic and naval phase.
The oligarchic coup of the Four Hundred — engineered partly through Alcibiades's manipulation of Persian subsidy promises — fails at Samos, where the fleet maintains Athenian democracy against its own city's government.
The oligarchs fall, Alcibiades is recalled, Athens wins at Cynossema — and mid-sentence in 411 BCE, fourteen years before the war ends, the History stops: Thucydides died before he could finish.