Homer
Although we know for sure that Homer Simpson is a fictional character, you might turn your nose up at hearing that many people believe the original Homer (a renowned author and poet) may be made up as well. One theory suggests that Homer was actually a blind woman, and that “his” stories were ghostwritten in order to gain more readers at the time. A more likely scenario is that Homer was a collective name for a group of bright and ambitious students with a vision to share.
John Henry
Because his story is shared via song, skeptics suggest that John Henry was never real to begin with. As the lyrics go, John Henry is revered for challenging a steam drill to see who can work quicker. John wins the challenge, but dies from exhaustion. The song helped to build unity when people feared that steam drills would take their jobs. Other than that, there is no recollection of a real John Henry or the story itself.