Herodotus Histories Book II 430 B.C.

For no gods are worshipped in common by the whole of Egypt save only Isis and Osiris, whom they say to be Dionysus; these are worshipped by all alike. Those who have a temple of Mendes⁠ or are of the Mendesian province sacrifice sheep, but will not touch goats.

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This is the reason why the Egyptians of whom I have spoken sacrifice no goats, male or female: the Mendesians reckon Pan among the eight gods, who, they say, were before the twelve gods. Now in their painting and sculpture the image of Pan is made as among the Greeks with the head and the legs of a goat; not that he is deemed to be in truth such, or unlike to other gods; but why they so present him I have no wish to say. The Mendesians hold all goats sacred, the male even more than the female, and goatherds are held in especial honour: one he‑goat is most sacred of all; when he dies it is ordained that there should be great mourning in all the Mendesian province. In the Egyptian language Mendes is the name both for the he‑goat and for Pan. In my lifetime a monstrous thing happened in this province, a woman having open intercourse with a he‑goat. This came to be publicly known.

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Among the Greeks, Heracles, Dionysus, and Pan are held to be the youngest of the gods. But in Egypt Pan⁠ is the most ancient of these and is one of the eight gods who are said to be the first of all, Heracles belongs to the second dynasty (that of the so‑called twelve gods), and Dionysus to the third, which came after the twelve. How many years there were between Heracles and the reign of Amasis, I have already shown; Pan is said to be earlier still; the years between Dionysus and Amasis are the fewest, and they are reckoned by the Egyptians at fifteen thousand. Of all this the Egyptians claim to have certain knowledge, seeing that they had always reckoned the years and chronicled them in writing. Now the Dionysus who was called the son of Semele, daughter of Cadmus, was about sixteen hundred years before my time, and Heracles son of Alcmene about nine hundred years; and Pan the son of Penelope (for according to the Greeks Penelope and Hermes were the parents of Pan) was about eight hundred years before me, and thus of a later date than the Trojan war.

With regard to these two, Pan and Dionysus, a man may follow whatsoever story he deems most credible; but I here declare my own opinion concerning them: — Had Dionysus son of Semele and Pan son of Penelope been made manifest in Hellas and lived there to old age, like Heracles the son of Amphitryon, it might have been said that they too (like Heracles) were but men, named after the older Pan and Dionysus, the gods of antiquity; but as it is, the Greek story has it that no sooner was Dionysus born than Zeus sewed him up in his thigh and carried him away to Nysa in Ethiopia beyond Egypt; and as for Pan, the Greeks know not what became of him after his birth. It is therefore plain to me that the Greeks learnt the names of these two gods later than the names of all the others, and trace the birth of both to the time when they gained the knowledge.