Goddesses of the Mabinogion

Rhiannon

Rhiannon was the daughter of Hefeydd Hen. She had three magical
birds that could wake the dead and lull the living to sleep.
This otherworld Princess was out riding her grey white horse 
when she was spotted by Pwyll, Prince of Dyfed.  He fell
instantly in love with her and she with him, although she
was already promised to Gwawl.
Pwyll tricked Gwawl into giving him Rhiannons hand in marriage.
When Gwawl's friend, Llwyd ap Cil Coed found out about the deceit, he 
put a curse on Dyfed which brought Rhiannon much trouble throughout 
her life.