Answer: Beowulf.
Explanation:
The main protagonist is none other than the titular character: Beowulf.
He is a warrior from the Geatish realm who is tasked by Hrothgar, the king to vanquish of monsters like Grendel and his mother. (Among other adversaries).
In this tale, we learn of the values of what it truly means to be a hero, as Beowulf showcases in strength, bravery, and most of all determination.