What I want to know is: why would a “German” gnome— complete with lederhosen— choose to haunt a farm in Missouri or anywhere else outsode of Europe? I mean, was there a mushroom famine we don’t know about that sent all these gnome immigrants to the New World? Of all the pictures I’ve seen of Ellis Island, I can’t say as that I’ve seen an actual gnome. Just sayin’.
The followers of those X-Files, the true believers, would say that these types of paranormal entities are not biological in the conventional sense nor bound to the geography and cultures of human society in the same way. Although "gnomes" would tend to appear where there are people of German, Swiss, or Austrian ancestry, leprechauns where those from Ireland or the British Isles live, elves for Scandinavians and Icelanders (devas or Rakshasas where Hindus or those from India are). More like a haunting from the astral realm. Even without too many shots of Jägermeister.
The banshee, on the other hand, crosses many cultures and costumes.