It took guts to invent the first balloon animals—literally! The very first weren’t rubber, latex, or mylar, they were made of intestines!

Long before Michael Faraday laid the groundwork for today’s modern versions back in 1824, balloons were commonly made by drying and inflating the bladders, intestines, and stomachs of animals.

As for who first came up with the idea of inflating entrails, there really is no way to know. We do know that inflated animal bladders and intestines have long been used for a variety of reasons, from jesters providing entertainment for royalty, to ancient Romans needing a vessel for storing and transporting wine, to Galileo testing the weight of air.

However, historians do seem to have an idea as to when the first balloon animals started to appear.

Ancient balloon animals

Experts believe that the first balloon animals were made by the Aztecs sometime in the 1300s, for reasons as far away from entertainment as you can imagine.

The material of choice was cat intestine, which would be cleaned, flipped inside-out, and sewn shut using a vegetable fiber thread that would form a sort of sticky adhesive when heated in the sun. This created an air-tight seal on the stitchings so that the intestines could later be inflated.

Once dried, the Aztecs would twist the intestines and blow air inside after each twist, trapping the air in the pocket before it.

Aztec balloon animals came in two shapes: dog and donkey, and each required days of work to complete.

Once finished, the intestine-balloon animals would be ceremoniously ascended to the top of the Aztec pyramid. In an offering of praise to the sun, the balloon animals were finally set on fire.

Aztec cat shortage

Shockingly, the Aztecs placed so much importance on their balloon animal offerings that they resorted to desperate measures after a contagious disease wiped out most of their cats. Rather than ceasing the balloon animal ceremonies, the Aztecs actually began to sacrifice humans for the sole purpose of collecting their intestines.

Present day balloon animals

Today’s balloon animals come thanks to the discovery of modern materials and the advances in mass manufacturing technology. However, that doesn’t mean that there aren’t a few inflated bladders still in use even today.

At the Fasching festival in Germany, it’s still customary to carry inflated pig bladders attached to the top of sticks. The same is done during Carnival in Spain.

In some old German neighborhoods, people still publicly announce that a pig has been slaughtered by hanging the inflated bladder of the animal in front of the establishment.

And inflated bladder balloons still appear right here in the United States. Done every year since 1875 for the Knights of Revelry Fat Tuesday parade, “Folly” still beats inflated cow bladders to ward away evil spirits on the streets of Mobile, Alabama.

Sources: Great Balloons! The Complete Book of Balloon Sculpting, Jean Merlin, Kaufman, and Greenberg, The Mayannaise Connection, Jacques Dupion Grouchard