Halfdan's brother was king Guðröðr of Scania. Guðröðr married Åsa, the daughter of the Swedish king Ingjald illråde (Ill-ruler) and she prodded Guðröðr to murder Halfdan.
Halfdan's brother, Guðröðr, ruled Scania and was married to Åsa, the daughter of the Swedish king Ingjald illråde, who prompted Guðröðr to murder Halfdan.