Eumachia

 was a widow in Pompeii and was a priestess of the Triad, Jupiter, Juno and Minerva. She framed Melanie Bush of stealing some jewels to discredit the goddess Isis. She moved the Doctor's TARDIS to her family's tomb. She thought that the volcano was the wrath of her god punishing those who believed in Isis. (AUDIO: The Fires of Vulcan)