The Goddess of the Many Names, Gudinnan med de många namnen

From at least the fifth century BCE onwards, Greek writers showed an interest in Egypt. Herodotus devoted one of the nine books of his history entirely to Egypt and was particularly interested in Egyptian religion, which he considered the source of Greek religious understanding. He identified Isis with Demeter and her husband and brother Osiris with Dionysus. The earliest evidence for the cult of Isis in the Greek world comes from Athens, where sometime in the fourth century BCE some Egyptians were given permission to acquire land and build a temple of Isis on it.

After the death of Alexander the Great in 323 BCE, Egypt was ruled by the Macedonian Ptolemaic dynasty. Their court was in Alexandria, and for most of the third century BCE they controlled significant territories outside Egypt, including islands in the Aegean. It was during this period that the cult of Isis spread most rapidly in the eastern Mediterranean. Isis was at this time accompanied not by Osiris but by the god Serapis. It is possible that this was when the first mystery cult of Isis began, although it is not until centuries later that we have unambiguous references to mysteries in literary texts and epigraphy.