Whats the Difference Between Beowulf and King Arthur?

Whats the difference between beowulf and king arthur?

Beowulf and King Arthur are two entirely separate characters, originating from different cultures and time periods. Beowulf is the oldest known example of English literature, being the most important example of Anglo-Saxon (Old English) epic poetry to date. Beowulf the character was a Scandinavian warrior-prince in what is modern day Denmark, helping the Danish king slay the monster Grendel, a "descendant of Cain," who has been killing his men. (There is more to this story, but that's the part most people are the most familiar with). It is believed to have been written between 700 and 1000 A.D, but the story it tells is purported to be much older, believed to have taken place long before it was written.
King Arthur was a British King believed (by some) to have lived in the late fifth and early sixth centuries. He supposedly led the defense of Britain against Saxon invaders, and established a powerful British hegemony over England, Scotland, Ireland, Gaul, and parts of Norway. While some historians believe there may have been an actual King Arthur directly referenced by these (and other) stories, who he was and what he may have ACTUALLY done are completely up for debate. There is no reliable historical evidence concerning his life.
Many different elements have become part of his legend, but there is no one definitive source or "final version" of his story. The "Sword in the Stone," Merlin, Excalibur, the Round Table, the Quest for the Holy Grail, Guinevere and Lancelot, Arthur's half-sister Morgan le Fay and their bastard/incestuous son/nephew Mordred, and Arthur's defeat and recuperation at the mystical island of Avalon have all become fairly well accepted as part of his story.

Beowulf evidently never married. Arthur was married to a woman who loved someone else. Beowulf had no children. Arthur had only Modred. Both strove to maintain high ideals/standards of honor. Beowulf is known for great feats of strength and heroism. Arthur is best known for pulling the sword out of the stone and then inspiring others to do feats of heroism. Each had a group of followers, but most of Beowulf's are not named, while we know the names of many of Arthur's knights. Both are mortally wounded fighting and die alone but for one comrade. The stories of both have roots in pre-Christian tradition, but the Arthurian stories are explicitly Christian, while the story of Beowulf only has some Christian overtones superimposed on pagan material.