This paper aims at collecting and investigating, from a rhetorical point of view, the speeches of the Achaemenid kings (from Cyrus to Xerxes) mentioned in Greek sources, with a special focus on Herodotus’ Histories. The many and heterogeneous discourses which this historian attributes to the different Persian kings (dialogues, private conversations, messages, letters and simple speech acts) are analysed and compared, and the research seems to point to some recurrent – and probably well-devised – patterns. The paper also takes into account the poetic speeches of Darius and Xerxes in Aeschylus’ Persians, and the scant evidence (a letter from Xerxes to Pausanias) transmitted by Thucydides.