The battle of Tanagra in 457 BC, narrowly won by Sparta, was an early engagement in what is referred to as the First Peloponnesian War between Sparta and Athens.  This conflict, which lasted more than a decade, was effectively the forerunner to the second, main Peloponnesian War of 431 – 404 BC. The two wars are separated chronologically by a period of tense peace, known as the Thirty Year’s Peace, for that was the intended length, but it only lasted thirteen years in practice.


Athens on the Offensive

Around the time of the battle of Tanagra, the Athenians began to wage full war against Spartan interests and allies across Greece.  Aegina, an island strategically located off the coast of Attica, and a member of the Peloponnesian League, was besieged and conquered by Athens.  The Aegineans were expelled and replaced by Athenian colonists. Sparta, which had no navy of significance, was powerless to aid Aegina directly, and the only succour it could offer was to resettle the refugees on the east coast of the Peloponnese in Cynouria near the Sparta/Argos frontier.  They would dwell there for fifty years until the final resolution of the wars.


The might of the Athenian navy was at this time unrivalled.  They sailed around the Peloponnese, raiding, burning and pillaging at will.  The Lacedaemonian dockyards at Gytheum were put to the torch, Boeae in southern Laconia was taken, and the island of Cythera, and Methome in Messenia were raided.  The Corinthian-settled town of Chalcis in Aetolia fell to the Athenians. Operations extended to the Ionian Sea, where the islands of Zacynthus and Cephallenia were conquered.  Under Pericles, a later expeditionary force took Naupactus at the mouth of the Corinthian Gulf and raided the Sicyonians.


Meanwhile, the Athenians also pursued war against Persia, including fighting as far away as Egypt.  The Persians sought Spartan aid, and by giving generous sums hoped to persuade the Spartans to invade Attica to draw off the Athenian forces in Egypt.  The money was to no use, for Megara was still allied to the Athenians, and the latter’s forces on Mt. Geraneia could effectively interdict movement from the Megarid into Attica.  Thus Sparta lacked good strategic options with which to respond to the Athenian moves.  


The Temple to Athena Aphaia on Aegina.


The Persian Threat Returns

The balance of power in the Eastern Mediterranean shifted in Persia’s favor when it eventually drove the Athenian forces from Egypt in 454 BC.  The Persian victory soon aroused concerns amongst the Greeks for whom Xerxes’ invasion was still a living memory. Naturally, there was widespread concern that the war between Athens and Sparta which divided the Greeks would invite another Persian invasion.  Perhaps to forestall such a development, Sparta and Athens agreed to a five year truce; left without Athenian support, Argos signed a thirty year peace treaty with Sparta which was now again unchallenged in the Peloponnese.


Athens and Persia signed a peace treaty in 449 BC.  Despite the removal of the Persian threat, the years that followed saw a marked weakening in the Athenian strategic position in central Greece.  Boeotia, which had been under Athenian domination since Tanagra, rose up. The Boeotian rebels defeated the Athenians at Coronea in 447 BC, taking many prisoners in the process.  In return for their exchange, Athens submitted to the rebels’ demands and left the region. Only a year later, the island of Euboea revolted, and soon thereafter Megara followed suit.  Athens faced simultaneous uprisings to the east and west, and had to make stark choices about where to concentrate its efforts. Pericles had already landed with an army in Euboea, and may have had difficulty returning to the Megarid.  Thus it came to pass that the Athenian garrison was overrun and slaughtered by the rebel Megarans who had received aid from Corinth and neighboring pro-Spartan cities. Now the way past Mt. Geraneia to Attica was open, and the Spartans, who were likely to have been privy to the planning of the Megaran rebellion, moved quickly to take advantage.


The Controversial King Pleistoanax

Pleistarchus, the heir to Leonidas, had died at a relatively young age in 458 BC and without leaving an heir of his own.  The Agiad kingship had passed to Pleistoanax, son of Pausanias (the former Agiad regent and victor at Plataea.) It was now King Pleistoanax who led the Spartan army into Attica, destroying farms and crops, and threatened Athens itself.  Pericles sued for peace, and probably also paid a hefty bribe to Pleistoanax (like father, like son it would seem), for the king simply stopped the army’s progress near Eleusis, and withdrew. The accompanying ephors must have been furious.  Some historians are more forgiving in their verdict, judging that Pleistoanax saw the opportunity for peace and grasped it. Yet if he thought he could get away lightly with defying the ephors, the king painfully misjudged. After his return, Pleistoanax was put on trial by the Gerousia, stripped of his kingship, and banished from Sparta.  He would spend decades in exile. 


The Thirty Years Peace

The terms of peace offered by Pericles, the Athenian leader, to Sparta in the wake of the invasion must have been well received by the dovish factions in Laconia for they agreed to them.  In simple terms, Athens would return those areas of the Peloponnese which it had taken, and acknowledge Sparta’s hegemony there in exchange for recognition of its own empire. It was a formal division of Greece into two political blocs, but notably it lacked broad consent – both Sparta and Athens ratified the treaty on behalf of their allies.  Now Athens’ allies were, with a few exceptions, more subjects to Athens than equal partners, but the Peloponnesian League was a significantly more egalitarian endeavour in 445 BC, and Sparta rankled the interests of powerful allies such as Corinth by not allowing them a say. Corinth, it should be remembered, had its own bitter rivalry with Athens in this period.  Likewise Megara, which had recently rejoined the League, and Boeotia, were fearful of Athenian territorial ambitions. Thus discontented allies of Sparta fell under a treaty to which they had never actually consented.


The peace treaty was to last for thirty years, and the intent seems to have been genuine, for both parties agreed to mechanisms for mediation and arbitration should a conflict arise.  Yet the treaty did not preempt every type of eventuality. For example with regard to third parties, or neutral states, the treaty allowed them to join either side as they pleased, but it explicitly did not allow switching of alliances.  It may not have been foreseen just how problematic issues concerning third parties might become in the future. To its authors’ credit though, the peace did last over a decade even though it was troubled from the outset by suspicion, mistrust, and long-term ambitions for total victory and hegemony by hawkish factions on both sides.  To be sure, Athens and Sparta remained politically opposed to each other throughout the period of peace.



The Revolt of Samos, 440 BC

Just a few years after entering into the treaty, Sparta nearly broke it.  Across the Aegean, Samos and Miletus, both members of the Delian League, clashed over the town of Priene to which they both made claim.  Samos was one of a handful of Athenian allies who were still independent, and not subjects of Athens. Miletus, on the other hand, had twice been violently subjugated by the Athenians, and the Ionian city was very much a vassal state.  Miletus had no fleet, its own having been destroyed by Athens, and so it appealed to Athens as its protector to arbitrate the dispute. The islanders of Samos refused the Athenian arbitration however, and the act of defiance did not go over well with Athens which probably had no strong views on Priene, but which considered the Aegean its dominion so to speak.


The Athenian reaction was swift.  Pericles led the navy to Samos and there took control of the island, deposing the oligarchs and establishing a democratic constitution.  The Samian oligarchs appealed to the Persians, and the local Satrap allowed them to employ a mercenary force from his territory. This force defeated the democratic government and the Athenian garrison, taking them prisoner.  Watching the events unfold other Aegean peoples seized the moment to revolt against the yoke of Athens. In the north, Byzantium rose in rebellion, and Mytilene signalled to Sparta that it would send its fleet to aid the Samians if Sparta would support the rebellion.


Samian envoys came to Sparta, urging the Peloponnesians to join the war against Athens.  Historians speculate about close links between certain Spartan and Samian families, because this was not the first time that Samos had attempted to lobby Sparta to liberate it despite a paucity of historical connection between the Dorian Spartans and the Ionian Samians.  Around 525 BC Sparta had intervened to oust the Samian tyrant Polycrates. Now, in 440 BC, the Samian appeals seem again to have found sympathy – probably with the hawkish factions which would have relished the opportunity to make war on Athens. Sparta decided to take the matter to the Peloponnesian League.  


Corinth and other allies were reluctant to fight a war in the Aegean.  Antipathy to Athens aside, the League lacked a navy strong enough to battle for control of the Aegean with Athens.  Strategically, the odds of victory were unfavorable, and the land-lubbering Spartans were in no position to lead a naval effort without the Corinthian fleet.  The proposal for war was rejected, and Samos was left to fend for itself. Predictably, the Athenians destroyed the rebels in 439 BC, and reasserted their hegemony of the Aegean.


The episode illustrated that the peace between Athens and Sparta was fragile, yet supported by a certain balance of power and strategic sense.  Corinth had settled the matter in favor of peace in the case of Samos, yet some years later Corinth’s own quarrels with an island far from Sparta would plunge the region into the greatest and longest war Greece had ever seen.




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