Halfdan

Halfdan (Old Norse: Halfdan, Old English: Healfdene, Medieval Latin: Haldānus, Proto-Norse: *Halbadaniz, "half Dane") was a late 5th and early 6th century legendary Danish king of the Scylding (Skjöldung) lineage, the son of king named Fróði in many accounts, noted mainly as the father to the two kings who succeeded him in the rule of Denmark, kings named Hroðgar and Halga in the Old English poem Beowulf and named Hróar and Helgi in Old Norse accounts.

According to the Chronicon Lethrense and Saxo Grammaticus' Gesta Danorum (Book 2), Halfdan had two brothers named Ro and Skat who also sought the throne. Both were killed by Halfdan. Saxo adds that his brothers' supporters were hanged and that Halfdan continued to reign with great cruelty, but that he reigned long and died peaceably in extreme old age.

The Ynglinga saga gives Halfdan (in this work also son of a king named Fróði) a brother named Fridleif and says both were great warriors but that Halfdan was the better of the two. This might have been a lead-in to a feud between the brothers if Snorri had been dealing with Danish matters rather than Swedish matters.

Snorri here only tells us that Halfdan attacked King Aun of Sweden and drove him into exile into Götaland. Halfdan then ruled Sweden for twenty years until he died in Uppsala of sickness and was buried in a mound.

...
Wikipedia