Interpretatio graeca is a Latin term for the common tendency of ancient Greek writers to equate foreign divinities to members of their own pantheon. Herodotus, for example, refers to the ancient Egyptian gods Amon, Osiris and Ptah as "Zeus", "Dionysus" and "Hephaestus".

The equivalent Roman practice was called interpretatio romana. The first use of this phrase is in Tacitus's Germania (ch. 43), in which he reports on a sacred grove of the Naharvali , saying "Praesidet sacerdos muliebri ornatu, sed deos interpretatione Romana Castorem Pollucemque memorant" ('a priest presides in woman's dress, but in the interpretation of the Romans, they worship the gods Castor and Pollux'). Elsewhere (ch. 9) he says that the chief gods of the ancient Germans were Hercules and Mercury—referring to Thor and Odin respectively.

Roman culture owed much to the ancient Greeks. The Greek colonies founded in Italy from the 8th century BCE contributed much to the young city, and later, when the Romans conquered the Hellenistic world, they adopted a new wave of Greek beliefs and practices. (See Romans and Greeks for details.) Where the two mythologies shared an origin, the interpretations came naturally; Zeus and Jupiter, for example, were both derived from Dyeus of the Proto-Indo-European pantheon. Elsewhere the fit was less precise, and the Roman god might add attributes borrowed from the Greek, but remain distinct: Mars retained his association with agriculture and fertility alongside his warlike attributes and, quite unlike the fearsome Greek Ares, was a benevolent and widely-revered cult figure.

The Romans interpreted Celtic and Near Eastern gods with equal facility. Cernunnos and Lugh were linked to Mercury, Nodens to Mars as healer and protector, and the Anatolian storm god with his double-headed axe became Jupiter Dolichenus , a favorite cult figure among soldiers.

Some Di Indigetes (native Roman gods), such as Janus and Terminus, had no Greek equivalent and so retained an independent tradition; a few, like Bona Dea, did the same despite sharing attributes with a Greek figure (in this case Artemis). Others, like the twelve assistants of Ceres, became mere adjuncts to imported Greek deities (here Demeter). Where the Romans had no equivalent figure, they did not hesitate to add foreign deities to their pantheon. Sometimes they would change the name: when Cybele was adopted from the Phrygians (the Greeks had previously interpreted her as Rhea), she was called Magna Mater deorum Idaea. Sometimes they would not: Apollo was called Apollo in both Greek and Latin.

See also: Greek mythology, Roman mythology, Similarities between Roman, Greek, and Etruscan mythologies

External link

• Essay on interpretatio romana