Njord (Niord) The Norse god of the sea and seafarers, and also a fertility god. Njord was a Vanir god. He went to live in Asgard after the Aesir/Vanir War. He took with him his twin children, Frey and Freya, both fertility gods. In some tellings, Njord’s first wife and the mother of the twins was Nerthus, his sister. As the Aesir did not approve of marriage between brother and sister, Njord had to leave Nerthus behind. Njord’s second wife was Skadi, goddess and giantess of winter.