How was Fridlevus II related to Halfdan?
Fridlevus II Fridleif (Ynglinga saga) was a son of Fróði of the Skjöldung (Scylding) lineage. In that work he was the brother of Halfdan and the father of Áli the Strong.
Aldgisl Aldegisel, Aldegisl, Aldgillis, Aldgisl, Aldgils or Eadgils (fl. c. 678) was the ruler of Frisia (as king or duke) in the late seventh century contemporarily with Dagobert II and a very obscure figure. All that is known of him is in relation to the famous saint that he harboured and protected, Wilfrid, but he is the first historically verifiable ruler of the Frisians. What the exact title of the Frisian rulers was depends on the source. Frankish sources tend to call them dukes; other sources often call them kings.