In theBrittanic Sea, opposite the coast of the Ossismi, the isle of Sena (Sein)
belongs to a Gallic divinity and is famous for its oracle, whose priestesses,
sanctified by their perpetual virginity, are reportedly nine in number.
They call the priestesses Gallizenae and think that because they have been endowed
with unique powers, they stir up the seas and the winds by their magic charms,
that they turn into whatever animals they want, that they cure what is
incurable among other peoples, that they know and predict the future, but that
it is not revealed except to sea-voyagers and then only to those traveling to
Mela: Description of the World (44.C.E.)
Read more on islands of priestesses in the Celtic world on this website.
of Michigan Press (1998)