 Whitley Stokes believed this latter spelling was due to a false etymology popular at the time.There have also been attempts by modern writers to link the Morrígan with the Welsh literary figure Morgan le Fay from the Matter of Britain, in whose name "mor" may derive from Welsh word for "sea", but the names are derived from different cultures and branches of the Celtic linguistic tree.The earliest sources for the Morrígan are glosses in Latin manuscripts and glossaries (collections of glosses).