Loki, the Norse trickster god, is credited with fathering a panoply of peculiar creatures (including the Midgard Serpent and the wolf Fenrir), but he is also on record as having given birth to one: Sleipnir, Odin’s horse. As the story goes, the gods commissioned a wall to surround their realm of Asgard, and promised an impossible fee to the builder if he completed the project within three months. Thanks to the aid of a powerful stallion the builder’s progress was rapid, and the gods demanded that Loki – who had suggested the stallion in the first place – sabotage the construction. He transformed into a mare and lured the stallion away, delaying the builder – actually a giant in disguise – from completing the project. When Loki returned he brought Sleipnir the colt as a gift to Odin, claiming to have given birth to it.
Although the story of Loki and Sleipnir is included in Wikipedia’s “LGBT themes in mythology” page, it is difficult to discern how it relates to contemporary terminology.Viking same-sex relations were stigmatized for the male receiving partner, adding a possible element of humiliation. While Loki does willingly engage in sex with a stallion, it is in the context of making amends for one of his mistakes, and there are no other direct references in Norse mythology to him sleeping with other male creatures; he does, however, change physical sex on several occasions. At least one prominent modern interpretation views him as bisexual, but – as ever – deities defy easy human categorization.