Podcast Summary: The Delian League – Ancient NATO?

Podcast: The Ancients (History Hit)
Host: Tristan Hughes
Guest: Professor Polly Low (University of Durham)
Release Date: March 26, 2026

Episode Overview

In this episode, Tristan Hughes is joined by Professor Polly Low to explore the origins, evolution, and legacy of the Delian League—an alliance of Greek city-states led by Athens in the 5th century BCE. The discussion centers on the League’s transformation from a mutual defense pact against Persian aggression into what many consider the first Athenian Empire. Together, they assess the League’s mechanisms, its successes and controversies, and how closely it resembles (or diverges from) modern alliances like NATO.

Key Themes and Discussion Points

Origins and Context of the Delian League

• Background: Emerged after the Persian Wars (c. 478/7 BCE), aimed at continuing the fight against Persian influence, liberating Greek cities in Asia Minor, and exacting revenge ([06:47]–[16:13]).
  • "The date of the creation of the league is 478/7 BCE. But we have to sort of go a little bit... back to the Persian wars." — Professor Low [06:47]
• Geography and Membership: Initially comprised a wide array of Greek city-states, especially islanders in the Aegean, peaking at about 300 members ([16:45]).
  • "It's actually really hard even to come up with a ballpark number for how many states are in this alliance at the start. It could be a hundred or so, but... probably about 300 at its biggest." — Professor Low [16:45]

Structure and Operation

• Leadership: Athens was the clear hegemon after Sparta's withdrawal ([13:18]).
• Contribution Model:
  • Unique dual system—members could contribute either ships (military support) or money (tribute) ([18:28]).
  • Over time, most states shifted to tribute payments, enabling Athens to control the combined military resources.
    • "Most states… by the end of the alliance, pretty much all of the states contribute money rather than manpower. And that means that Athens ends up with a monopoly on military power..." — Professor Low [18:28]

Early Operations and Justifications

• Campaigns: The League's early actions maintained a focus on Persian adversaries—expelling Persians from strategic locations, e.g., Aion and Anatolian coast ([19:51]–[21:16]).
• Motivations: Mixed motives—noble ideals (liberation, revenge) coexisted with Athenian self-interest and proto-imperial expansion.
  • "They're liberating in scare quotes Greek cities from the Persian Empire. But then the Athenians become the people who are in charge of those cities." — Professor Low [21:46]

Dissent, Repression, and Imperial Transformation

• Attempts to Leave and Athenian Response:
  • Thasos, Naxos, and Carystos—all forcibly retained and subjected to penalties ([23:23], [28:20]).
    • "Thucydides… says this was the first state... to be enslaved by the Athenians. And that language of slavery is the language that... has previously characteristically been used of what the Persian Empire does." — Professor Low [23:23]
  • Demonstrates the shift from voluntary alliance to enforced subjugation.
• Shifting Contributions: By the late 450s, only a handful of major allies (Chios, Lesbos, Samos) still sent ships; the rest paid tribute ([26:22]).

The Treasury Move and Symbolism

• Relocation of the League’s Treasury: From Delos to the Acropolis in Athens, c. 454 BCE ([30:33]).
  • Seen as a key moment of imperial assertion and practical control:
    • "The center of the League is now in Athens and no longer in Delos." — Professor Low [31:27]
• Official Justification: Security from Persian raids; real motive likely Athenian control ([31:50]).

Major Setbacks and Turning Points

• The Egyptian Expedition (c. 460s BCE):
  • Ambitious but disastrous campaign to aid a rebellion against Persia in Egypt—heavy losses for Athens and the League ([36:10]).
  • "It's a disaster... quite a sort of slow motion disaster." — Professor Low [36:10]

Decline of the Anti-Persian Purpose and Rise of Empire

• End of Persian Hostilities: Possible but contested "Peace of Callias" in the late 450s, marking the practical end of anti-Persian operations ([48:05]):
  • "If it happened... it's a sort of non aggression pact." — Professor Low [48:05]
• Using Tribute Against Greeks: Allied tribute increasingly funded wars against other Greeks—not Persians—a major shift in mission and perception ([46:55], [47:46]).
  • "We were quite happy to be part of this alliance. When we were fighting the Persians, that's fine. But then we saw that the Athenians have stopped fighting the Persians and instead they're trying to oppress other Greek states." — Professor Low (citing Mytileneans) [47:46]

Mechanics of Control and Imperialism

• Cleruchies: Establishment of Athenian settlements/land holdings in rebelling allies as both punishment and method of control ([54:05]):
  • "If a city tries to rebel and fails... the Athenians will seize the land... and distribute it among Athenian citizens." — Professor Low [54:28]
• Building Projects: Debate over whether League funds were used to glorify Athens (Parthenon, etc)—accusations of “embezzlement” ([60:27]):
  • "Plutarch's Life of Pericles... goes all in on saying this is the most scandalous thing..." — Professor Low [61:44]

The Samian Revolt: Culmination of Empire

• **Samos, once a close ally (still contributed ships), revolted in response to Athenian heavy-handedness in a local dispute ([62:06]).
  • The revolt was violently suppressed, marking a psychological turning point:
    • "...if you can't even rely on this island anymore, then something's... changed." — Professor Low [66:16]
  • Thucydides later notes Athenians feared they might lose the Empire at Samos ([67:05]).

Notable Quotes & Timestamps

• "Most states... by the end of the alliance, pretty much all of the states contribute money rather than manpower. And that means that Athens ends up with a monopoly on military power..."
  — Professor Polly Low [18:28]

• "They're liberating in scare quotes Greek cities from the Persian Empire. But then the Athenians become the people who are in charge of those cities."
  — Professor Polly Low [21:46]

• "This was the first state... to be enslaved by the Athenians."
  — Professor Polly Low (on Naxos, quoting Thucydides) [23:23]

• "If a city tries to rebel and fails... the Athenians will seize the land... and distribute it among Athenian citizens."
  — Professor Polly Low (on cleruchies) [54:28]

• "If Samos had been successful, that could have been the end of the empire."
  — Professor Polly Low (citing Thucydides’ view) [67:05]

Comparison to Modern Alliances (NATO Parallel)

• The hosts leave the question open for listeners: The Delian League began as a defensive alliance but grew increasingly compulsory and coercive, diverging from the voluntary, self-determined model characteristic of NATO ([70:26]).
  • "We'll leave that to you... how much could you link the story today with the functioning of NATO or... not a right tree to climb..." — Tristan Hughes [70:26]

Conclusion & Scholarly Reflections

• Key Debates: When the League became an Empire—options include the Naxos revolt, the moving of the treasury, or the Samian revolt. Professor Low leans toward the Samian Revolt as a crucial marker, but cautions that the turning point likely varied among different members ([67:46]–[69:33]).
  • "I'm increasingly keen on the Samian revolt... but... depending where you are in this empire, the key moment might have come at a very different point." — Professor Low [68:18]
• Final Assessment:
  • The Athenians likely sought to maximize power and profit from the outset, rather than maintaining pure defensive intentions ([69:44]).

Further Reading Mentioned

• Recent Translation of Thucydides (with introduction and notes by Professor Polly Low, translated by Robin Waterfield) [70:09].

For Listeners

This episode vividly illustrates how alliances can morph into empires under the guise of collective security, highlighting both ancient complexities and resonances for today. Whether the Delian League was an ancient version of NATO or something fundamentally different is left, fittingly, as an open-ended question for history enthusiasts.