The event when Onela was slain was probably a historic event. Even though it is only briefly mentioned in Beowulf, it occurs extensively in several Scandinavian sources where it is called the "Battle on the Ice of Lake Vänern". For example, Snorri Sturluson wrote: "Onela rode Raven, as they rode to the ice, but a second one, a grey one, hastened, wounded by spears, eastwards under Eadgils." [...] "In this fight Onela died and a great many of his people. Then king Eadgils took from him his helmet Battle-boar and his horse Raven." (Although, in Snorri's text the names are in their corresponding Old Norse forms).