Diplomatic Finesse: The Peloponnesian League, Anti-Tyranny Doctrine, and Non-Intervention in Ionia

Despite the undoubted effectiveness of its professional army, Sparta did not always resort to war to solve its problems with neighboring city-states.

In fact, the Spartans demonstrated an acute appreciation of their limits and vulnerability, which in turn gave rise to a predominantly cautious foreign policy that relied heavily on effective diplomacy.

In consequence, Sparta produced the first known "permanent" alliance system in history: the Peloponnesian League.

Sparta, like most other cities in ancient Greece, initially followed an aggressive policy toward her neighbors. In two lengthy and bitter wars in the late 8th and early 7th century, Sparta subjugated its western neighbor, Messenia.  Exhausted from this struggle, Sparta thereafter sought more subtle means of hegemony.

When during the mid-6th century, Sparta came in conflict with its northern neighbor Tegea and suffered a significant defeat, Sparta made the—at the time astonishing—decision to seek not a temporary but a permanent peace. The remarkable initiative is attributed by ancient sources to a certain Spartan citizen, Chilon, whose reputation for wisdom was so great that he was regularly counted among the "seven wise men" of the ancient world. Chilon is even credited with the famous sayings carved in stone at Delphi: "Know thyself" and "Everything in moderation." This second saying seems particularly relevant, because it was probably recognition of Sparta's limited resources that induced a change in policy. The complete victory over Messenia had created a constant internal threat in the form of a subject population likely to revolt. The treaty of non-aggression and mutual support negotiated with Tegea not only prevented an expansion of the problem posed by the threat of Messenian revolt, but bound the Tegeans to provide support to Sparta in the event that the Messenians did revolt. After the precedent had been set with Tegea, Sparta went on to make similar treaties of mutual defense with a series of other cities in the Peloponnese. Although little is known about the workings of this League, it is clear that despite a certain recognition of Spartan leadership, a majority vote was needed for concerted action, that Sparta had only one vote, and at various times members of the league acted against Spartan policy with impunity. In short, this was not a Spartan Empire disguised as a League (as the Delian League was to be later under Athenian hegemony).

Sparta's fundamentally cautious foreign policy also kept Sparta out of the military entanglements on the far side of the Aegean. The expansion of Persia in Asia Minor resulted in a number of Greek colonies being conquered or turned into vassal states of the Persian Empire. A number of these cities rose up in revolt against Persia and requested aid from the cities of the Greek mainland. Sparta's refusal to support these cities can be seen as callous or even "unpatriotic," but it reflected the fact that at this time (late 6th and early 5th century BC), Sparta effectively had no fleet and so no way of supporting a war on the other side of the Aegean.

Last but not least, the conservatism of Sparta's 6th and 5th century foreign policy is reflected in the fact that Sparta was extremely reluctant to move against Athens—despite rising pressure for support from the city-states chafing under Athens' increasingly oppressive and arrogant hegemony. Effectively, its allies in the Peloponnesian League pushed Sparta into the wars we know as the Peloponnesian Wars.

The most important deviations from this cautious policy all served the preservation of democracy. In the second half of the 6th century, Sparta won a reputation as the bulwark of democracy against tyranny by repeatedly coming to the assistance of democratic elements in other cities and helping them to depose their tyrants. Plutarch claims, for example, that Sparta was instrumental in deposing the tyrants in Corinth, Naxon, Athens (Hippias) and Sikyon. Modern historians have questioned this list, but admit that there had to be some basis of truth for the Spartan reputation. They also suggest that the motivation for these interventions was the tendency of tyrants of this time to ally themselves with Persia. In this case, the Spartan foreign policy of intervention in the internal affairs of other cities can be seen as preventive self-defense. Another explanation, of course, is that the tyrants tended to be populist leaders who catered to the mob. As such, they were viewed as more "dangerous" to the conservative Spartans than "democracies" dominated by aristocratic elites.

Whatever Sparta's motives for opposing tyrants, Sparta demonstrated consistent and passionate opposition to Persian designs on Greece in this period. Sparta made itself ridiculous—in the eyes of the powerful Persian monarchs—by "warning them" against enslaving Greeks. The master of an empire stretching from modern India to modern Turkey had never heard of Sparta. He asked who these people were who dared "warn" him. He was even more astonished to learn that they were masters of just two small, relatively infertile valleys in Greece. When the Persians later sent ambassadors demanding submission to Persia, the Spartan Assembly responded by throwing the ambassadors in a well—an unprecedented breach of diplomatic immunity. When the invasion finally came, Sparta was elected by the informal alliance of anti-Persian cities to take command. Sparta sent one of her own kings, Leonidas, with an advance guard of 300 citizens and larger contingents from other members of the anti-Persian alliance, to try to halt the invasion at the Pass of Thermopylae. When a traitor betrayed their position, King Leonidas released the other allies to return to their homes, but he and his Spartans, supported voluntarily by 700 Thespians, remained in position and died to a man in a gesture of commitment. Less than a year later, Sparta fielded an army composed of what must have been every able-bodied man in the city-state and sent it north of the Isthmus—a significant fact because it demonstrated Spartan commitment to defending all of Greece and not just the Peloponnese. This army met the significantly superior Persian land forces still threatening Greek independence despite the defeat of the Persian fleet at Salamis the previous fall. In spite of the deplorable performance of most of the Allied contingents, the Spartans and Athenians under Spartan leadership managed to defeat the much larger Persian forces and end the direct threat of Persian invasion.

When in the following decades, Athenian arrogance led other Greek cities to pressure Sparta into opposing Athens, Sparta went to war reluctantly and with the clear statement that Athens could prevent hostilities if Athens would "let the Greeks go free." As too often in history, it was Sparta's success after nearly a third of a century of conflict that led ultimately to its own destruction. The defeat of Athens made Sparta the dominant power in Greece. The power and the temptation to abuse that power was too great even for Sparta's vaunted discipline.