Folcwald (which means leader of folk or people) is the father of Finn, a legendary Frisian king. He is mentioned in Widsith and in Beowulf; a passage from Beowulf as translated by Seamus Heaney (lines 1089—1090) reads:
In the range of persons mentioned in the Widsith, only Finn's father is named, which seams to be particular. Maybe he was a distinctive person in those times (dark Middle Ages), a great king or warrior like his son. However this is unclear as written sources are missing.