Frigg and Freyja common origin hypothesis
Due to numerous similarities, some scholars have proposed that the Old Norse goddesses Frigg and Freyja descend from a common entity from the Proto-Germanic period. Regarding a Freyja-Frigg common origin hypothesis, scholar Stephan Grundy comments that "the problem of whether Frigg or Freyja may have been a single goddess originally is a difficult one, made more so by the scantiness of pre-Viking Age references to Germanic goddesses, and the diverse quality of the sources. The best that can be done is to survey the arguments for and against their identity, and to see how well each can be supported."
Unlike Frigg but like the name of the group of gods to which Freyja belongs, the Vanir, the name Freyja is not attested outside of Scandinavia, as opposed to the name of the goddess Frigg, who is attested as a goddess common among the Germanic peoples, and whose name is reconstructed as Proto-Germanic *Frijjō. Similar proof for the existence of a common Germanic goddess from which Freyja descends does not exist, but scholars have commented that this may simply be due to the scarcity of evidence outside of the North Germanic record.