In the parodos of Aristophanes’ Frogs, the entrance of the mystic chorus is preceded by its chant of Ἴακχ’ ὦ Ἴακχε, | Ἴακχ’ ὦ Ἴακχε (316–17), the same cry that was traditionally voiced in the Iacchus procession from Athens to Eleusis during the Great Mysteries. It is the aim of this contribution to peel back the emotional and cognitive layers of what may have been the first audience’s response to this religiously, politically, and historically significant sound. What did the theatrical mimesis of this ritual vocalization, which for several years prior to the play’s production in 405 BCE had been “muted” due to the Spartan occupation of Attica, make the Athenian audience think, feel, and remember? To answer this question, philological and historical methods of inquiry native to classical studies as well as cross-cultural perspectives drawn from sound, religious, and memory studies are employed. A central argument is that Aristophanes’ evocation of the Iacchus cry gives sonic expression to the cultural and political nostalgia and longing that inform Frogs, in particular, nostalgia for the Athenian-led victory over the Persians at Salamis.