Our recent lunar eclipse was nothing that the Franks hadn’t seen before. The learned and literate believed in the Aristotelian egocentric “concentric spheres” model of the cosmos, which held sway until the 16th century. While we chuckle at the spheres, the model does put the moon in orbit around the earth, and thus does explain that eclipses are caused by the intersection of the earth, moon, and sun.
The understanding of a lunar eclipse by the common people was far more lively.
The common folk believed that the moon was under attack by some malevolent spirit or demon. Before you chuckle at that, consider the evidence: the moon, on the night it is full, so powerfully bright and white, is suddenly and unexpectedly turning an ominous red. This mystifying transition happens slowly, yet inexorably, turning the moon, normally a festive friend, the only real light after sundown, into a shadow of its former self.
What to do if your friend is under attack? You help, of course, to fight off the attacker! Rabunus Maurus, writing in the early 9th century, gives us an eyewitness account:
Horns were blaring as if calling for war, and pigs were grunting. People were throwing arrows and missiles at the moon while others were hurling fire from all direction at the sky.
The Church frowned on this sort of heavenly interaction, but could not stamp out the practice. After all, like a barking dog that “wins” when someone walks along the fence and then vanishes, the crowd defending the moon won every time!
I found this tidbit in “Daily Life In the World Of Charlemagne,” by Pierre Riche. This is a really good book, with short chapters that cover a wide variety of topics. Riche does an amazing job of mining the sources to show us at least a glimpse of the common people.