I found this British Library link interesting.

The poem must have been passed down orally over many generations, and modified by each successive bard, until the existing copy was made at an unknown location in Anglo-Saxon England.

There are many that would dispute the idea that Beowulf is an oral composition; it bears many marks of a literary, or written, work. In general, scholars are moving away from the oral composition theory for Old English poetry. While there was undoubtedly a rich tradition of oral composition in Anglo-Saxon society, most of the works that survive are probably literary. Which is not to say that the story of Beowulf wasn’t told orally, but that the poem that we know today is a literary (i.e., written) composition. (But we don’t know that the story was told orally. There are no references to the Beowulf story in other works (such references would indicate that it was well known and oft-told), while there are good indications that other poets cribbed passages from it, hinting that it was known as a great poem among the lettered elite.)

Dave Wilton - 24 October 2012 02:59 AM

There are no references to it in other works, which would indicate that it was well known and oft-told,

I find this line ambiguous.  Is the fact that there are no references to it that indicates that it was well known and oft-told or is it that references to it in other works would be indicative of its being well known and oft-told?  The structure of the sentence suggest the former to me but common sense and the greater context would make me think the latter.  A suggested rewrite, if the latter, would be:

There are no references to it in other works, references which would indicate that it was well known and oft-told

Corrected.