Nekyia

In ancient Greek cult-practice and literature, a nekyia (Ancient Greek: ἡ νέκυια) is a "rite by which ghosts were called up and questioned about the future," i.e., necromancy. A nekyia is not necessarily the same thing as a katabasis. While they both afford the opportunity to converse with the dead, only a katabasis is the actual, physical journey to the underworld undertaken by several heroes in Greek and Roman myth.

In common parlance, however, the term "nekyia" is often used to subsume both types of event, so that by Late Antiquity for example "Olympiodorus ... claimed that three [Platonic] myths were classified as nekyia (an underworld story, as in Homer's Odyssey book 11)".

A number of sites in Greece and Italy were dedicated wholly or in part to this practice. "The Underworld communicated with the earth by direct channels. These were caverns whose depths were unplumbed, like that of Heraclea Pontica." The most notable was the Necromanteion in the northwestern Greek town of Ephyra. Other oracles of the dead could be found at Taenaron and Avernus. Such specialized locations, however, were not the only places necromancy was performed. One could also perform the rite at a tomb, for example. Among the gods associated with the nekyia rite are Hades, his wife Persephone, Hecate, and Hermes (in his capacity as psychopompus – one who escorted souls to Hades).

The earliest reference to this cult practice comes from Book 11 of the Odyssey, which was called the Nekyia in Classical antiquity. Odysseus was instructed to "make a journey of a very different kind, and find your way to the Halls of Hades ... across the River of Ocean". There he consults the soul of the priest and prophet Teiresias about the means to return home to Ithaca, in a setting of "ghosts and dark blood and eerie noises, like a canvas of Hieronymous Bosch". He sacrifices a ram and an ewe so that "the countless shades of the dead and gone" would "surge around" him and then he meets and talks to the souls of the dead.

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