There is a medical textbook from the Middle Ages, written in old English, and titled

Bald's Leach Book.

And I know what you might be thinking.

Yes, leeches were indeed once used in ancient medicine, but don't worry.

The Leach in Leach Book is believed to derive from an old English word meaning something

closer to prescription.

It was a book of remedies.

There was one for treating

shingles that involved combining the barks of 15 different trees, and other for treating headaches

by binding a stalk of cross-wark to the head with a handkerchief, the kind of stuff you'd expect

to find in an ancient book of what in those days passed as medicine. And the remedies weren't just

for us humans. Bald's Leech

book even had one for a horse in pain, though this remedy was a bit more like a spell. It

involved inscribing a phrase on the handle of a dagger, and if that's not weird enough, try this one

on for size. The author notes in the text that the cause of the horse's pain may have been an elf.

These little creatures, the stuff of ancient folklore and superstition, were once very much a part of many people's belief systems and social realities.

They lived invisibly among rural people. They had supernatural powers. Elves were real to many of our ancient

ancestors. They were out there. They were worthy of serious mention in a medical book. They were

thought to commonly afflict humans and livestock with things like sharp internal pains

and forms of mental illness. They were even known to abduct people. Sometimes they worked their evil deeds with

magical weapons, other times it was sorcery or alchemy. So how do we get from these early

depictions and beliefs of mythical, scary, dangerous creatures to Christmas? What do elves even

...