Allison Meier traces tales of Rat Kings ”to the plague years, when rats were spreading the deadly disease, and a whole nest that lived so close they became inextricably twisted together was a horrible omen of death”:
One of the largest “specimens” is kept by the Mauritianum Museum in Altenburg, Germany, and has 32 rats mummified grotesquely together, appearing as if some of the creatures died along the way and continued to be pulled along with the monstrous horde. This idea of the Rat King is such a viscerally vivid image that it’s creeped its way into culture, such as with the many-faced “Mouse King” in E. T. A. Hoffmann’s novella The Nutcracker and the Mouse King. However, there’s still no proof that the Rat Kings actually exist and are not just cryptozoological hoaxes. But what is more unsettling, a conjoined mess of rats scratching through the dark, or a person gathering up to 32 dead rats and knitting all their tails together with their hands just to freak people out?