Was Beowulf based on a true story?

Beowulf is a fictional character in an annonymously penned epic poem contained in a single manuscript known as the Nowell Codex. Since little is known about the author of this Anglo-Saxon writing from between the 8th and 11th century, no one can say for certain that the character was not based in part on a living person, but there is no evidence that suggests Beowulf is not fictional.