Though you are absent, I feel your presence,
A space in the landscape where you would be,
An echo returning from this very place
In the Otherworld where you followed Pryderi.
Did he go there to claim his birthright
In the country you left to be with us here?
Did you follow to give him your blessing
Leaving only the wraith of a riderless mare
To haunt the borders between us and Annwn?
For now we live with your memories lingering
Like elusive scents from a summer that’s gone
Or the sounds of your birds so sweetly singing.
In the unwoven woods Manawydan awaits you
Keeping the keys for the expected day
To open the gates when you will come riding
On a shining white horse in bright array.
In the Third Branch of the Mabinogi tales Rhiannon follows Pryderi into an enchanted fort and they are carried off to the Otherworld. Manawydan eventually manages to bring them back. According to the plot of the medieval tale an enchantment has been cast over their land by an otherworld sorcerer and Manawydan also breaks that spell. But I have interpreted these plot mechanisms as a means to explain the comings and goings of Rhiannon – here and in an earlier tale – from the Otherworld, thereby emphasising the mythological aspects of the tales with devotional intent.
To leave a devotional message for Rhiannon visit her shrine HERE
awenydd.cymru 
Your interpretation is as enchanting as Rhiannon. It deserves deep reflection.
Indeed it’s an enchanting poem – beautiful and evocative and haunting.
‘Leaving only the wraith of a riderless mare’ makes me think back to your essay in ‘The Grey Mare in the Hill’ where you speak of Rhiannon reverting to her wild and uncanny horse nature when she goes into the fortress with Pryderi.
I’ve been thinking about Llywd Cil Coed recently and his role as an enchanter, abductor and obfuscator wielding mist… seems to share alot of resemblances to Gwyn… maybe this is the nature of Annuvian deities.
Perhaps in some senses Rhiannon reverts to her Annuvian nature here, although her intention may be to help Pryderi who doesn’t possess the wisdom of his father and hasn’t won the title Pen Annwn? Not too sure. There’s a very complex mythology at work and I’m only beginning to gain a small understanding of it.