Chaucer called the fairy-king Pluto and the queen Proserpina.

Again, to hark back to the other romances, we have found the word _fay_
attached to the name of King Arthur's sister Morgan. Nothing is more
remarkably certain than the close and constant association in mediaeval
lore of the fairies and the fairy-world with the Arthurian cycle of
romance;[74] King Arthur's sister was Morgan le Fay, whose son by Ogier was
Merlin; and the romance of _Huon of Bordeaux_, which relates these facts,
though strictly belonging to the Charlemagne cycle, contains the account of
Oberon's bequest of his realm to King Arthur. Chaucer, whatever other
doubts he may have had, was convinced on this point:--[75]

"In th' olde daiès of the King Arthoure,
Of which that Bretons speken gret honoure,
Al was this land fulfild of fayerye;
The elfqueen with hir joly companye
Dauncèd ful ofte in many a grenè mede;
This was the olde opinion as I rede."

Now the Arthurian legends ultimately derive from Celtic tales, which must
be supposed to have travelled from Wales into France by way of
Brittany--Little Britain, or Armorica--in the eleventh and twelfth
centuries; for there are Welsh versions independent of the Breton forms,
though closely akin. Students of early Celtic literature have not as yet
agreed about the historical relations between Welsh and Irish
stories--whether the Welsh imposed their mythology and heroic legends on
the Irish, or _vice versa_; but the general similarity between them is
undeniable, and easily explicable by a common Celtic source.

Everything, then, points to the Celtic legends as the chief origin of the