Overview
Skuld was a princess of Scandinavian legend who married Heoroweard and encouraged him to kill Hroðulf (Hrólfr Kraki) in Hrólfs saga kraka. The accounts of her vary greatly from source to source. Skuld is derived from the Old Norse verb skulla, "need/ought to be/shall be"; its meaning is "that which should become, or that needs to occur". Other similarly named characters appear in the Skjöldunga saga and the Gesta Danorum, as well as the Chronicon Lethrense.
Hrólfs saga kraka
Hrólfs saga kraka tells that one Yule, Helgi (appears as Halga in Beowulf) was visited by an ugly being while he was in his hunting house. No person in the entire kingdom allowed the being to enter the house, except Helgi. Later, the thing asked to sleep in his bed. Unwillingly he agreed, and as the thing got into the bed, it turned into a dark elvish woman, who was clad in silk and who was the most beautiful woman he had ever seen. He raped her, and made her pregnant. Helgi forgot the woman and a couple of days after the date had passed, he was visited by the woman, who had Skuld on her arms. The daughter would marry Hjörvarđr (Heoroweard).
Much later, when her half-brother Hrólfr Kraki was King of the Danes, Skuld began to turn her husband against Hrólfr. Under the pretext that they would wait three years before paying the accumulated tribute at one time, Skuld assembled a large army which included strong warriors, criminals, elves and norns. She was a great sorceress and used seiðr (witchcraft) to hide the great muster from Hrólfr and his champions. They then arrived at Lejre one Yule for the midwinter blóts, with all the weapons hidden in wagons to ambush the king at night. A battle ensued and, in the account found in Gesta Danorum, Bödvar Bjarki fought in the shape of a spirit bear until he was awakened by Hjalti. To overcome him, Skuld cast the most powerful spell to resuscitate her fallen warriors and after a long fight Hrólfr and all his eleven champions fell, with the sole exception of Vöggr who promises to avenge the king.
As Hjörvarđr was also killed in the battle, Skuld became the Queen of Denmark but did not rule well and only for a short time. Bödvar Bjarki's brothers Elk-Froði and Thorir (Þorir) Houndsfoot went to Denmark to avenge their brother. The Swedish queen Yrsa gave them a large Swedish army headed by Vöggr. They seized the wicked elf queen by surprise, just as she had suddenly attacked the king, tying her arms so she could not use her magic arts.
From Wikipedia (CC BY-SA 4.0).