Ragnar Lothbrok [" Hairy Breeks"] is a semi-legendary Viking, portrayed, in broad terms by Ernest Borgnine in Douglas' movie. The general story is that he was captured by Aeilla, and thrown into a flooded tower with skates, rays, and God knows what, where he died [Borgnine jumped, once properly armed with his passport to Valhalla, into a wolf pit].
Where it gets interesting is the next part. Supposedly, three of Ragnar's sons swear vengeance, invade Northumbria [and subsequently more of England], and kill Aeilla. One of Ragnar's sons was supposedly Ivar the Boneless-who IS a histoical figure. So maybe, Ragnar's story is true.
Historically, there's no evidence a Viking named Ragnar led the raid on Lindisfarne. Vikings generally wore chain mail when they fought, and their shields were a bit souter. They also used the common infantry formation of the time- the shield wall.
But you gotta love the Vikings! What a great heaven. Fight all day, drink all night 'til Ragnarok. And all the waitresses look like St. Pauli Girls! ODIN!