Leonidas: King of Sparta, Hero of Thermopylae

March 22, 2026·1 hr 4 min·3 clips

Cleomenes' rule collapses into bribery, religious violations, exile, and a violent death.

1. The Ancients episode centers on Leonidas, king of Sparta, and the Battle of Thermopylae in 480 B.C. 2. Tristan Hughes hosts Dr. Andrew Baylis, Associate Professor of History at the University of Athens and author of The Rise and Fall of an Ancient Superpower. 3. The episode asks what survives about Leonidas before Thermopylae and how Sparta's royal politics shaped him. 4. Baylis says Herodotus is the earliest surviving source and only mentions Leonidas when he reaches Thermopylae. 5. He adds that Diodorus and Plutarch also focus on Leonidas at Thermopylae, which leaves the earlier story thin. 6. Baylis notes that Herodotus travelled to Sparta and may have heard an official Spartan version from people like Gorgo. 7. He says there is no classical Spartan coinage, no inscription bearing Leonidas' name, and no secure archaeological object for him. 8. The conversation then turns to Alexandridas, Leonidas' father, and the strange fertility problems in the Spartan royal houses. 9. Herodotus' account says the ephors told Alexandridas to replace his wife, but he refused before taking a second wife. 10. That arrangement produced Cleomenes by the second wife and Dorieus, Leonidas, and Cleombrotus by the first. 11. Baylis explains that Sparta was a diarchy, with the Agiad and Eurypontid kings sharing military, priestly, and council duties. 12. He describes Spartan kings as front-line leaders guarded by the 300 hippies and, in some cases, Olympic champions. 13. The episode also covers the Spartan upbringing, which begins at age seven and runs to roughly 20 or 30 for most citizens. 14. Baylis says royal heirs were usually exempt, while Leonidas and his full brothers likely completed the state training. 15. He distinguishes the homoioi, the Spartan equals, from the perioikoi who handled trade and manufacture, and the helots who worked the land. 16. Cleomenes' reign is presented as a period of campaigns against Argos, Athens, and internal rivals like Demaratus. 17. Baylis recounts the scandals around Delphi, Argive sacred space, and Cleomenes' exile before his death under house arrest. 18. He says Leonidas then inherits a throne shaped by a power vacuum, with Demaratus replaced by Leotychides and Persia looming in the background. 19. The tone is explanatory and argumentative, with Hughes pressing Baylis for source criticism, family detail, and political context. 20. Listeners interested in Spartan politics, Greek kingship, and Thermopylae will get the most from it; listeners wanting a simple battle recap may skip it.

As heard by us

A measured look at Leonidas that places Thermopylae inside Spartan politics and the Persian advance.

Leonidas is set against Thermopylae, but the discussion keeps widening to the Persian advance in late summer 480 B.C. and the political world around Sparta.

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Why you'd press play

You want Leonidas beyond the last stand.

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