In Roman literature, Erichtho (from Ancient Greek: Ἐριχθώ) is a legendary Thessalian witch.
In the epic by the poet Lucan, Pharsalia (VI, 507—830), she summons a spirit to reveal to Pompey the Great's son, Sextus Pompeius, the outcome of the Battle of Pharsalus.
She is also mentioned by Dante Aligheri in his Divine Comedy (Inferno: IX 23), where Virgil, possibly alluding to a lost medieval legend, tells of having been earlier compelled by her to descend into the deepest part of hell to bring back a spirit.
Erichtho is also a character in Johann Wolfgang von Goethe's Faust, Part 2, Act 2, as the first character to speak in the Classical Walpurgisnacht scene (II.1). Erichtho's speech to open that scene is the introduction of the Witches' High Sabbath. It immediately precedes the entrance of Mephistopheles, Faust, and Homunculus to the rites that result in Faust's Dream Life Sequence as a knight living in a castle with Helen of Troy (until the death of their child shatters the fantasy and Faust returns to the physical world for the conclusion of the play).