Today's Passage
This passage marks the formal beginning of the Peloponnesian War proper in 431 BCE.
Crawley Translation (1910)
Immediately after the affair at Plataea, Lacedaemon sent round orders to the cities in Peloponnese and the rest of her confederacy to prepare troops and the provisions requisite for a foreign campaign, in order to invade Attica. The several states were ready at the time appointed and assembled at the Isthmus: the contingent of each city being two-thirds of its whole force. After the whole army had mustered, the Lacedaemonian king, Archidamus, the leader of the expedition, called together the generals of all the states and the principal persons and officers, and exhorted them as follows:
Modern Translation
Following the incident at Plataea, Sparta immediately dispatched orders throughout the Peloponnese and to all allied territories, commanding them to prepare soldiers and supplies necessary for a campaign abroad, with the intention of invading Attica. At the designated time, each state arrived at the Isthmus with two-thirds of their total military strength ready for action. Once the entire force had assembled, Archidamus, the Spartan king commanding the expedition, convened all the state generals, leading officials, and officers to deliver an address.
Historical Context
This passage marks the formal beginning of the Peloponnesian War proper in 431 BCE. The 'affair at Plataea' refers to the Theban attack on this Athenian ally, which served as the war's immediate catalyst. Archidamus II, the Spartan king, is mobilizing the Peloponnesian League for the first major invasion of Attica, Athens' home territory. The Isthmus of Corinth served as the traditional mustering point for Peloponnesian forces. The specification of 'two-thirds' of each state's forces indicates this was a major but not total mobilization, leaving some troops to defend home territories. This moment represents the transition from diplomatic tensions to open warfare between the two great alliance systems of classical Greece.
Key Themes
Annotations & References
The Peloponnesian League
Sparta's alliance system, formally established in the 6th century BCE, bound member states to provide military support. Unlike Athens' empire, it was theoretically a voluntary confederation, though Sparta's military dominance ensured compliance. Members retained internal autonomy but followed Sparta's foreign policy.
Learn more →Archidamus II
The Eurypontid king of Sparta (r. 469-427 BCE) who initially opposed war with Athens, warning of its length and unpredictability. Despite his caution, he dutifully led the first invasions of Attica. The first phase of the war (431-421 BCE) is named the 'Archidamian War' after him.
Learn more →Ancient Greek Military Mobilization
Greek city-states maintained citizen militias rather than professional armies. Mobilization required advance notice for citizens to prepare equipment and provisions. The two-thirds levy allowed states to maintain home defense while contributing to collective campaigns.
Learn more →The Isthmus Strategy
The Isthmus of Corinth was the strategic chokepoint between the Peloponnese and central Greece. It served as a natural assembly point for Peloponnesian forces and later became the site of defensive walls during various conflicts in Greek history.
Learn more →Parallel Ancient Sources
Plutarch: Life of Pericles (33.1-2)
Describes Pericles' defensive strategy of withdrawing the Attic population within Athens' walls rather than meeting the Peloponnesian invasion in the field, showing the Athenian response to this mobilization.
Read passage →Diodorus Siculus: Library of History (12.42)
Provides a parallel account of the war's outbreak and initial Peloponnesian preparations, though with less detail than Thucydides about the specific mobilization process.
Read passage →Xenophon: Hellenica (2.2.3)
Though describing later events, shows similar Spartan mobilization procedures, demonstrating the consistency of Peloponnesian League military organization throughout the classical period.
Read passage →Discussion Questions
- What does the specification of 'two-thirds' of each state's forces reveal about Greek strategic thinking and the balance between offensive operations and homeland defense?
- How does Archidamus' role as a reluctant war leader who nevertheless performs his duty reflect broader themes of political obligation in Thucydides?
- Why might Thucydides emphasize the formal, procedural aspects of going to war (orders, assembly, speeches) rather than jumping directly to military action?
- What can we infer about the nature of the Peloponnesian League from this passage's description of mobilization procedures?