Early Dragon

Does the sword that Beowulf uses against the Dragon have anything to do with the spat earlier in the story?

Beowulf uses Unferth's sword against the Dragon, it breaks. Does its breaking have anything to do with Unferth's challenge earlier in the tale?
Well whatever. Does the sword fail because of its connection to its original master's quarrel with Beowulf?

The name Unferth means “Unfaithful”. He may be a representative of the traditional evil councilor in traditional tales, like the traditional treacherous seneschal in French tales, or the traditional treacherous grand vizier in Arabic tales.

Remember there were lots of tales about Hrothgar and Hrothwulf that have not come down to us and Unferth may have played a part in them.

In “Beowulf” Unferth’s part is to rudely charge Beowulf with losing in a swimming match. Unferth seems to repent after Beowulf slays Grendel, and provides him with a sword. But the word breaks. I don’t think this is supposed to have anything in particular to do with Unferth. Though perhaps it is just what we should expect of a sword provided by Unferth, even in good will.

It is traditional in some folktales that a monster or troll can only be killed by a particular weapon. Having another weapon break is a dramatic way of pointing to this. Then Beowulf gets the proper weapon and kill’s Grendel’s dam.

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