According to the Prose Edda, Snotra is one of the Ásynjur.

Her name is clearly derived from the adjective snotr meaning "wise" or "graceful". More than that the Prose Edda does not tell us.

Þrettánda Snotra, hon er vitr ok látprúð. Af hennar heiti er kallat snotr kona eða karlmaðr sá er vitr maðr er. http://www.hi.is/~eybjorn/gg/gg4par33.html

"The thirteenth [of the Ásynjur] is Snotra. She is wise and graceful. From her name a wise woman or man is called snotr."

She is mentioned neither in the Poetic Edda nor skaldic poetry nor, indeed, in any other extant Norse or West-Germanic source.

Due to this lack of evidence it has been suggested, for example by Rudolf Simek in his Dictionary of Northern Mythology, that Snotra was an invention of Snorri Sturluson. While this is certainly possible it is unclear why Snorri would invent a goddess out of whole cloth, especially since Snotra is the 13th entry on his list. One would think he would have been happy with 12 Ásynjur since he states that there are 12 Æsir.

A possible explanation is that Snotra was originally an alternative name for another goddess, perhaps Frigg, and taken by Snorri to be a separate goddess. Having nothing else to go by Snorri then informs his readers that Snotra is "wise and graceful", based simply on her name.

It is also conceivable that Snorri had access to an authentic, if sparse, oral tradition which has not come down to us in any other source.

References

• Eysteinn Björnsson (ed.). Snorra-Edda: Formáli & Gylfaginning : Textar fjögurra meginhandrita. 2005. http://www.hi.is/~eybjorn/gg/
• Simek, Rudolf . Dictionary of Northern Mythology. 1993. Trans. Angela Hall. Cambridge: D. S. Brewer. ISBN 0-85991-369-4. New edition 2000, ISBN 0-85991-513-1.

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