Is the Rat King Real or Simply an Urban Legend?

Two rats aren't likely to get tangled, but 12? Then you're much more likely to have an ugly scene entailing some dead rats on your hands. Alan Tunnicliffe Photography / Getty Images

Few phenomena are as strange, grotesque and captivating as the rat king — a creature that has fascinated and unsettled people for centuries.

But what is a rat king, and is it real or simply a metaphor born of tales and urban legend?

What Is a Rat King?

A rat king is a rare occurrence in which a group of rats — sometimes as few as seven rats, sometimes more — becomes bound together at the tails, often by horse hair, sticky substances or even blood.

This bizarre phenomenon usually occurs in confined spaces such as sewers, basements, or nests, where rats are close enough for this entanglement to happen.

Some scientists speculate that the rats' grasping reflex causes them to inadvertently tangle and stay bound for an extended period, especially when panicking or injured. Once caught, the rats may remain alive, struggling together to survive — a biological and social nightmare tangled into one creature.

Historical Reports and Specimens

The earliest report of a rat king dates back to the 16th century, and naturally occurring rat kings have reportedly been found across Europe, including Germany and France. The most famous instance was a rat king discovered by an Estonian farmer, which was later preserved and displayed in a museum.

Many specimens are on exhibit in natural history museums today, some verified through X-ray images or ray images, revealing entangled bones and genuine rat king formations.

These findings suggest that, while rare, rat kings are not entirely fictional. In fact, a rat king found in recent decades reignited interest and debate among scientists and the public.

Modern Debates and Theories

Some believe that the appearance of rat kings is the result of rats being caught in freezing weather, where skin, urine and feces solidify into a tangled mass. Others argue that the phenomenon may have been created for curiosity cabinets or exhibitions.

Despite skepticism, the rat king has become symbolic of societal and urban decay, often appearing in media, video games, literature and even children’s stories (notably in "The Nutcracker," where the Rat King is a key character and boss figure).

Living or Dying?

Are rat kings alive when found? Sometimes, yes.

There are accounts of rat kings being discovered while still breathing, though many die soon after due to starvation or infection. Some rat kings may form around a central nest, with the tangle acting as a kind of unintended throne or monster guarding the food supply.

Such events highlight the brutal, survivalist world rats inhabit — and their unintentional link to urban mythology.

Could It Happen to Other Animals?

Interestingly, rat kings aren't the only tangled tales in the animal kingdom. Similar events have been documented with squirrels, leading to the term "squirrel king." These incidents also involve tails becoming entangled by external substances.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.