The name **IAO** (Ιαώ in Greek letters) shows up in a surprising number of places in antiquity, and the evidence spans inscriptions, magical papyri, and philosophical writings. It’s essentially a Greek rendering of the Hebrew divine name **Yahweh** — but it got reinterpreted and absorbed into several religious and magical systems.

Here’s where we actually *find* it:

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## **1. Greek Magical Papyri (PGM) — Egypt**

* **Date:** mostly 2nd century BCE – 4th century CE

* **Location:** Found in Egypt, written in Greek (often with Coptic or Demotic phrases).

* **Context:** IAO appears as a powerful name in spells, invocations, and hymns.

* Example: *PGM V.96–172* includes “IAO SABAOTH ADONAI” alongside other divine names.

* These were syncretic — combining Greek, Egyptian, and Jewish divine names in magic.

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## **2. Jewish Inscriptions in the Greco-Roman World**

* **Elephantine, Egypt (5th c. BCE):** Aramaic papyri mention Yahweh (YHW) — not “IAO” yet, but this is the root. Later Greek speakers transliterated YHWH as Ιαώ.

* **Leontopolis, Egypt:** Inscriptions from the Jewish Temple there (2nd–1st c. BCE) possibly used the form IAO in Greek translations or explanations.

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## **3. Diodorus Siculus (Greek Historian)**

* **1st century BCE** — In *Bibliotheca Historica* (Book 1.94), he says the Jews worship a god called “Iao,” which he equates with the planet Saturn.

* This is one of the earliest literary identifications of Yahweh’s name in Greek form.

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## **4. Philo of Byblos / Phoenician Tradition**

* Some fragments claim Phoenician priests used “Ieuo” or “Iaō” as a high divine name, possibly through cultural contact with Israelites.

* Whether this is authentic tradition or Hellenistic reinterpretation is debated.

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## **5. Gnostic Texts**

* **Nag Hammadi Library (Egypt, 4th c. CE copies of earlier works)**: “IAO” appears as a name for one of the archons or emanations in Sethian and Valentinian systems — sometimes as a form of the Demiurge.

* In Gnostic cosmology, IAO could be:

  1. A corrupted form of the true god’s name

  2. A powerful but ignorant ruler of the material realm

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## **6. Greek Philosophical Sources**

* **Clement of Alexandria** (*Stromata*, 5.6) discusses “IAO” as the sacred name of the Jewish god.

* **Origen** and other early Christian writers also mention pagans using the name in magical contexts.

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## **7. Archaeological Amulets and Gems**

* Found in **Egypt, Syria, and the Mediterranean**, dating 1st–4th centuries CE.

* Engraved with “ΙΑΩ” often alongside other divine names, zodiac signs, or protective symbols (ankh, ouroboros).

* These show IAO was part of a living magical practice, not just literature.

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### **Geographic Range of Evidence**

* **Egypt** — biggest trove (magical papyri, amulets, Jewish communities)

* **Syria & Phoenicia** — inscriptions and literary references

* **Rome & Greece** — magical gems and early Christian polemics mentioning the name

* **Cyprus & Asia Minor** — syncretic cult inscriptions

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If you map it historically:

1. **Israelite Yahweh (YHWH)** →

2. **Aramaic YHW** in diaspora communities →

3. **Greek Ιαώ** in translations and magic →

4. Recast into **Hellenistic magic & Gnostic cosmology**

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If you want, I can give you a **chronological evidence chart** showing exactly where and when the name “IAO” is attested, from its earliest Aramaic roots to its late antique magical uses. That way you can see its path from temple worship to occult grimoires.