World-changing431 BCE – 404 BCE · 27 years
Peloponnesian War
Greece · Sicily · Aegean Sea
Athens and Sparta's 27-year war destroyed Greek city-state independence and inaugurated Western history's first superpower conflict.
Estimated casualties
50K – 100Kestimated dead
HEADLINE100K — the single figure used on the map
431-404 BCE; plague casualties included
SOURCEThucydides; Clodfelter
What happened
Athens' imperial expansion and Sparta's land-based conservatism clashed (431-404 BCE). Athenian democracy vs. Spartan oligarchy became the war's ideological backdrop. Pericles' plague devastated Athens (430-426 BCE), killing a third of the population including Pericles himself. Armies devastated farmland; naval battles determined supremacy. Athens' Sicilian Expedition (415-413 BCE)—an attempt to expand westward—failed catastrophically: the fleet was destroyed; 40,000+ soldiers died. Sparta's victory (404 BCE) ended Athens' dominance, though Sparta's hegemony lasted only decades. Roughly 100,000 died across the war.
Why it mattered
The Peloponnesian War marked the end of Classical Greece's independence; Philip of Macedon later conquered the weakened city-states. Thucydides' war history became the template for political realism and 'might makes right' analysis. The war demonstrated that democracy's internal debates could undermine military coherence. Athenian intellectual and cultural dominance (philosophy, drama, architecture) survived political defeat. The war remains a paradigm for how rising powers and established powers clash—the 'Thucydides Trap.'
Belligerents4
- Athens
- Sparta
- Corinth
- Syracuse
ON THE MAPAthens (Delian League)Sparta (Peloponnesian League)
Conflict graph
SUB-CONFLICTS · 29
- Battle of Potidaea432 BCE
- Battle of Methone431 BCE
- Battle of Naupactus429 BCE
- Battle of Patras429 BCE
- Battle of Spartolus429 BCE
- Battle of Mytilene428 BCE
- Battle of Corcyra427 BCE
- Battle of Olpae426 BCE
- Battle of Tanagra426 BCE
- Battle of Pylos-Sphacteria425 BCE
- Battle of Solygeia425 BCE
- Battle of Delium424 BCE
+ 17 more in the atlas.
Sources
- Wikipedia: Peloponnesian War
- Thucydides, History of the Peloponnesian War
- Wikipedia — text reused under CC BY-SA 4.0
Open in the atlas →Seeks the timeline to 431 BCE and opens this record.
Cite as: Peloponnesian War (431 BCE – 404 BCE). War Atlas. https://waratlas.org/c/peloponnesian-war · Sources & methodology