Ancient History & Civilisation

APPENDIX D The Peloponnesian League in Thucydides


©1. “Peloponnesian League,” a modern term for the ancient formula “The Spartans and the Allies,” invites the Voltairean comment that it was actually neither Peloponnesian nor a league (as the Holy Roman Empire was to Voltaire neither holy nor Roman nor an empire). It was not a “league” in our sense because the allies were bound individually by treaty to Sparta, not to each other, and indeed sometimes fought against each other (4.134; 5.81.1). The official name is known to us both from narrative sources such as Thucydides, who also abbreviates it to “the Peloponnesians” alone (1.105.3), and from a tiny handful of documentary inscriptions.

©2. Precisely how Sparta’s original military alliances with such Peloponnesian cities as Corinth (always her most important ally), Elis, and Tegea were translated into a composite League is not known for certain, though the transformation had definitely occurred by the time of the Persian Wars of 480-79 and probably as many as twenty years before that. The turning point may well have been the fiasco of about 506, when Sparta under her wayward and autocratic king Cleomenes I lost the support of the majority of her allies on the very brink of a combined attack on Athens. Cleomenes’ Spartan co-king led the defection at the prompting of the Corinthians. Thereafter only one king at a time was empowered to lead a Spartan or allied army, and Sparta required the allies’ formal consent before undertaking such a League expedition (see “Mechanisms,” below).


©3. Several cities within the Peloponnese, most conspicuously Argos, were never members of the League, and some cities outside, above all Megara and those of the Boeotian federation, sometimes were. At its largest, within the half century following the Peloponnesian War, the League extended as far north as Chalcidice, but never outside mainland Greece. It is useful therefore to distinguish between the wider Spartan alliance (1.31.2; 2.9.3), on the one hand, and its inner core or circle comprised by the Peloponnesian League members, on the other. Occasionally there is a doubt as to the status of an ally, most conspicuously in the case of Athens after the Peloponnesian War in the years 404 and immediately following. We know that the “hegemony clause” (discussed below) was applied to Athens by Sparta, but it does not follow that Athens was incorporated fully within the League structure any more than Argos had been after the battle of Mantinea (5.79-80.1).

Corinth: Appendix D Map, AY; Elis, Tegea: Appendix D Map, AX.

Argos, Megara, Boeotia: Appendix D Map, AY.

Chalcidice: Appendix D Map, locator.



©4. Conversely, there were episodes, indeed whole periods, in which a Peloponnesian League ally or allies defected from or even fought an outright war against Sparta: such a period was 421-18, when Corinth, Mantinea, and Elis4a revolted from Sparta and allied themselves with Argos. The Boeotians and the Megarians, however, significantly refused to join the Argive-led coalition in the belief that “the Argive democracy would not agree so well with their aristocratic forms of government as the Spartan constitution” (5.31.6).


©5. In technical language the Peloponnesian League was a hegemonic symmachy. Each of Sparta’s allies swore to have the same friends and enemies as their hegemon (“leader”) and to follow the Spartans wherever they might lead them. In practice, Sparta’s leadership was restricted by the obligation to persuade a majority of allied delegates at a duly constituted League congress to follow her in declaring war or in making peace, and to do so on her terms. But only Sparta could summon such a congress (1.67.3; 1.87.4; 1.119-125.1), so that she could never be committed by her allies to a policy she opposed (1.88.1; 1.118.2). On the other hand, she did fail to persuade a majority on more than one occasion (e.g., 1.40.5). Allies, moreover, had one important opt-out clause: they were obligated to obey a majority congress decision “unless the gods or heroes stand in the way” (5.30.3)—unless, that is, they could legitimately invoke a prior and overriding religious obligation.

©6. Unlike Athens, Sparta did not impose on her allies tribute in cash or kind (1.19), partly because traditional hoplite-style warfare (see Appendix F) was much less expensive than maintaining a large trireme navy (see Appendix G, ©12 and 13, and Appendix J, ©6), but also because Sparta lacked the necessary administrative mentality or infrastructure (1.141.6). Allies were required by Sparta to contribute a certain number or proportion of their troops to a League force, and Sparta provided the officers both to levy and to command the contingents stipulated (2.75.3). Most importantly of all, however, by a variety of informal means, and chiefly through the overt or covert support of favorable oligarchic regimes in the allied cities (1.19; 1.144.2; cf. 1.18.1; 5.31.6), Sparta took great care to ensure that her League allies would routinely fulfill her wishes.

©7. For almost 150 years (c. 505-365), therefore, the Peloponnesian League quite satisfactorily realized the twin aims the hegemon set for it: to serve as the means whereby Sparta could behave on the international stage as one of the two (or three) great Greek powers, and to throw a protective cordon around the vulnerable domestic basis of all Spartan life and policy, the Helots. In 371, however, the Spartans and their allies were decisively beaten at Leuctra in Boeotia by their former allies the Thebans; the now-undisguisable shortage of Spartan citizen manpower (see Appendix C, ©8) was not the least cause of their disastrous defeat. In its wake the brilliant Theban commander Epaminondas conducted a massive invasion of Laconia, the first-ever invasion of Laconia by land by a foreign power since the formation of the Spartan state some three to four centuries earlier. By freeing the Helots of Messenia, and so destroying the economic basis of the Spartan army’s superiority, and by fortifying the Messenians’ old stronghold on Mt. Ithome (1.101.2-3; 1.102.1-3; 1.103.1; 3.54.5) to ensure the independence of their new (or reborn) city of Messene, Epaminondas put an end to Sparta’s “Great Power” status for good. The Peloponnesian League was an early casualty of Sparta’s enforced weakness, simply melting away into oblivion well before Sparta’s second major defeat in hoplite battle at the hands of Epaminondas, at Mantinea in 362.

Mantinea, Elis: Appendix D Map, AX.

Paul Cartledge
Clare College
Cambridge University
Cambridge, England

Boeotia, Leuctra, Thebes: Appendix D Map, AY.

Messenia, Mt. Ithome (Ithome): Appendix D Map, BX.

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