According to the narrative, Hnæf was the brother of Hildeburh and brother-in-law of Finn, who ruled the Frisians and was killed during a Danish expedition to Frisian territory.
The father-son pair Hoc and Hnæf has been associated with the historical Alamannic noblemen, possibly of Nibelung extraction, Huoching (d. 744) and Hnabi (d. 788), the founder of the Ahalolfings. This suggestion was first made in 1849 by John Mitchell Kemble in History of the Saxons in England (p.419). If the Old English legendary characters have been influenced by these historical characters, this would set the late 8th century as a terminus post quem for the date of Beowulf.[1]
↑Hans Jänichen, Die alemannischen Fürsten Nebi und Berthold und ihre Beziehungen zu den Klöstern St. Gallen und Reichenau, Blätter für deutsche Landesgeschichte (1976), pp. 30-40.