Gefjun, is an Aesir maiden in Norse mythology, protector of virgins, to whom belong all who die unmarried, and goddess of family and happiness. She is considered as pure as the morning dew.
It is said that Odin instructed her to make a beautiful land for the people. King Gylfi of Sweden, as a traveling woman who had pleased him by singing, gave her as a reward as much land as four oxen could plow in day and night.
However, she, coming from the Aesir family, took four oxen from Jötunheim, which she had born to a giant, and harnessed them to the plow. The plow went so deep that it tore land away from Sweden, whereupon the oxen pulled it away through the sea.
Gefjun is said to have been married to Skjöld, the son of Odin, and to have lived with him in Lethra, the Danish royal seat on Zealand.
In Loki's "Shame Speeches" (Lokasenna), Gefjun wonders why the Aesir are angry with Loki. She says it is his way of blaspheming and accuses him of hating the Aesir.
Loki now attacks Gefjun, saying that a dwarf gave her jewelry and she immediately wrapped her thighs around him. Odin then warns Loki not to arouse Gefjun's resentment, for she knows as much about the fate of the world as the chief god himself.