In Norse mythology, Nanna Nepsdóttir or simply Nanna is a goddess associated with the god Baldr. Accounts of Nanna vary greatly by source. In the Prose Edda, written in the 13th century by Snorri Sturluson, Nanna is married to Baldr and the couple produced a son, the god Forseti.

Baldr is a god in Germanic mythology. In Norse mythology, he is a son of the god Odin and the goddess Frigg, and has numerous brothers, such as Thor and Váli. In wider Germanic mythology, the god was known in Old English as Bældæġ, and in Old High German as Balder, all ultimately stemming from the Proto-Germanic theonym *Balðraz.