Guðröðr of Skåne

Guðröðr was a legendary 7th century Scanian king who according to the Ynglinga saga was the brother of Halfdan the Valiant, Ivar Vidfamne's father.
The Ynglinga saga tells that Guðröðr married Åsa, the daughter of the Swedish king Ingjald Ill-ruler. She backtalked Halfdan so that Guðröðr killed him, and having done so, she arranged the death of Guðröðr himself. Then she fled back to her father in Sweden.
Guðröðr was succeeded by his nephew Ivar Vidfamne who avenged his father and uncle, and conquered Sweden and other countries.

Hervarar saga and Hversu Noregr byggdist give more information about his brother Halfdan the Valiant and his son Ivar Vidfamne, and by implication about Guðröðr himself.

Hversu Noregr byggdist gives Halfdan the Valiant's father as Harald the Old, his grandfather as Valdar and his great-grandfather as Hróarr (i.e. the Hroðgar of Beowulf).

Hervarar saga provides the information that Halfdan's mother was Hild, the daughter of the Gothic king Heiðrekr Ulfhamr, the son of Angantyr who defeated the Huns.