The Earth Goddess.

There is an IE Earth-goddess. The original form of her name does not seem recoverable, but was probably something like 'Mother-Earth'. My main sources are Meriam Robbins Dexter's articles in EIEC ('Earth', 'Earth Goddess', 'Goddess') as well as Robert Grave's The Greek Myths. Direct quotes are taken from the article 'Goddess' (p. 174).

In Slavic, she was Mati Syra Zemlja ('mother moist earth'). She "is linguistically related with Latvian Zemes Mate, Lithuanian zemyna". In the south we encounter her as the Phrygian, Thracian and Greek Semele (the mother of Dionysus by Zeus). The Zemes/zemyna/Semele word would all seem to be reflexes of PIE *dheghom, 'earth'.

Elsewhere in the IE world, she is found under different names. She is apparently the Germanic Nerthus, a watery goddess whose sacrificial victims were despatched by drowning. Nerthus is said to be etymologically connected to the Roman goddess Nerio, Greek anar, as well as Old Indic nara-, connected with either a word for 'man', or in Polome's estimation, cognate to Greek nerteros, 'lower, belonging to the lower world'.

For myself, I also add Hel, the goddess of the underworld in Norse heroic literature. English 'hollow' is related to 'Hel'. She and her realm are thought of as damp and frosty.

In the Mediterranean and Anatolia, she is greatly changed. Her more overt mother-goddess functions are reassigned to Rhea and Kore/Demeter and whatever underworld functions she had were moved to Persephone.

The myth of Semele has ever-jealous Hera encouraging Semele to ask Zeus to show himself to her in his full glory. When Semele asks Zeus to do so, he appears to her in his full celestial glory, with the result that she is consumed by fire. Zeus rescues their unborn son and sews him up into his thigh. Once the infant Dionysus is born, he's kidnapped by Hera and torn to shreds, only to be reconstituted by his grandmother, the mother-goddess Rhea.

For myself, I also note a parallel here in the Kalevala to Lemminkainen, in that this beer-loving lout of a boy was sewn-back together by his mother too, much as was Dionysus by his grandmother. Whatever the quality of the Uralic evidence, there is a suggestion that a myth of the torn-apart child being reconstituted and revivified by his mother may be PIE, or at least a part of the common mythological stock of northern and northeastern Europe.

What's interesting is that Zeus is here, as no where else, made to be an explicity solar deity. His burning glory consumes the earth (-mother), and from the flames, he brings forth a child. There is an interesting parallel here with the IE sacrifice of the '8-legged' mare or cow, where a pregnant mare or cow is sacrificed to one aspect, and her unborn offspring sacrificed to another.

One thought is that Dionysus might be a very late, feminized version of an IE god. If the women could not have a powerful goddess, they could content themselves with an effeminate woman-raised god of wine and orgiastic frenzy.

Graves correctly sees Dionysis as combining a number of myths. He is also wrong, I think; he wants to relate 'Semele' to 'Selene', the moon goddess.

As for what the IE earth-goddess was, I'm not entirely sure. At a fundamental level, she was simply the earth personified -- something that seems to be a human universal. She would also seem to have underworld functions, and may indeed have been the earliest version of the goddess Hel.

Mark.