In Finnish mythology, Will-o'-wisps were thought to be guardians of great treasure buried by fairies. The treasures could be located with a mythical fern seed. A supposedly rare phenomenon. In reality, fern flowers did not have seeds and instead had spores to reproduce. That single fact put the stories of the Aarnivalkea, Will-o'-wisp, into question.
So how about Wales? The British? The former assumed the Will-o'-wisps to be a fairy light belonging to goblins called the púca and the latter associated them with jack-o'-lanterns. The Irish lent the existence to leprechauns or to the folktale of Stingy Jack. So many stories, so many similarities, yet so many breaking differences. A keen mind would recognize that history was distorted with authenticity. Not everything was a hundred percent accurate.
It didn't have to be. Those similarities had to be mean something.
BAM!
BAM!
BAM!