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# Peace of Nicias

## Overview
The Peace of Nicias (421 BCE) was a treaty intended to end the first phase of the Peloponnesian War (the Archidamian War) between Athens and Sparta. Signed in March 421 BCE, it was supposed to last 50 years but effectively collapsed within a few years. @t[=421 BCE]

## Key Facts
- Date: March 421 BCE @t[=421 BCE]
- Parties: Athens and Sparta (and their respective allies)
- Negotiators: Nicias (Athens) and King Pleistoanax (Sparta) [^3]
- Context: Ended the Archidamian War (431–421 BCE), first phase of the Peloponnesian War @t[431 BCE..421 BCE]
- Duration: Nominally 50 years; effectively ~6 years

## Terms
The treaty's specific provisions, recorded by Thucydides (5.18–19), included: [^1]
- Sparta to return Amphipolis to Athens
- Athens to release the 292 prisoners captured at Pylos and Sphacteria (425 BCE), including at least 120 Spartiates @t[=425 BCE]
- Mutual non-aggression for 50 years
- Disputes to be settled by arbitration
- Temples and sanctuaries throughout Greece to be open to worshippers from all cities
- The oracle at Delphi to regain its autonomy

## Failure
- Key Spartan allies (Corinth, Boeotia) refused to sign
- Neither side fully implemented the terms; Sparta failed to deliver Amphipolis, which remained under local control
- Alcibiades undermined the peace by forming the Quadruple Alliance with Argos, Elis, and Mantinea (420 BCE) @t[=420 BCE] [^2]
- The Battle of Mantinea (418 BCE) further destabilized the settlement @t[=418 BCE] [^1]
- The Sicilian Expedition (415–413 BCE) effectively ended any pretense of peace @t[415 BCE..413 BCE] [^2]

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[^1]: Thucydides, *History of the Peloponnesian War* 5.18–19
[^2]: Kagan, D. *The Peace of Nicias and the Sicilian Expedition* (Cornell, 1981)
[^3]: Thucydides, *History of the Peloponnesian War* 5.17; Plutarch, *Life of Nicias* 9