Gylfaginning, which is part of Snorra Edda, was composed in Iceland in the 13th century, and holds the stories of many of the Pre-Christian myths of northern Europe. It is believe to have been composed by the Icelander Snorri Sturlusson. Snorra Edda consists of three separate parts, Gylfaginning, Skaldskápamáland Háttatal, all functioning together as a greater work and guide for the aspiring medieval poet and storyteller.
Frigg is the most important goddess among the Æsir. Her husband is Óðinn and she is the mother of Baldr. As described in Skáldskaparmál 18 and 19, she has a dress which enables her to transform into a falcon. Similar to the older Germanic traditions concerning Óðinn, the figure of Frigg as Óðinn’s wife seems to have an ancient origin with Frigg having been venerated as a goddess of women, relationships and love.
For more, see:
Simek, Rudolf (2007), Transl: Angela Hall. Dictionary of Northern Mythology. Cambridge: D.S. Brewer. pp. 93-94
Steinsland, Gro (2005), Norrøn Religion. Myter, Riter, Samfunn. Oslo: Pax Forlag. pp. 236-239
(Contributed by Liv Marit Aurdal.)
Main text: Gylfaginning