Everyone under-rates this movie because they don't understand the nature of the Group Dynamics behind the plot, or the meaning behind it's ending. First, the Arab "Eben," so named by the Viking Buliwif, is from the highest Civilization on the planet at the time, Muslims in Bhagdad. In 922 AD, he is sent off to the area now known as Ukraine, infested with Bear Cult tribes, and saved by Norsemen, where he's adopted as one of their troupe to become a warrior through a ritual of "magical-thinking," thrown bones. That he learns their language from observation isn't that far-fetched as we know from today's savants, or ERB's John Carter's first adventures on Mars/Barsoom, and his deeds with the Vikings are numerous and novel - he can put sounds to writing, refashions his sword, uncovers the creatures in the "Flaming Verm" are "men," and deduces they live in a cave, things the Vikings did not do, or could not do for or by themselves. After the killing of the Bear Cult's mother, Buliwulf's death is lamented by a Viking's suggestion that his life should somehow be put in writing. That "Eben" should be worthy of God, it is alluded that he eventually pens the Viking Saga known as "Beowulf".
As a fictitious back-story to historical actualities, this is Brilliant Escapism with all the tenets of Group Dynamics, with all the clues in place, and a joke on all you avid movie going intellectuals and efficienados out there who think you know what you're watching. Not one review anywhere says what I've just pointed out, and Chrichton must have been laughing like a drunken Viking at the folly behind the volume of comments missing his point.
ENCORE Cable Channel is running it occasionally, now that "Beowulf" is running on SHOWTIME. Watch it again and try and prove me wrong.