The tombs at Tuna el-Gebel are ornate. Dating back to the Ptolemaic dynasty of ancient Egypt, one chamber in the massive necropolis offers a curious glimpse into ancient Egyptian belief. Square windows, framed with ornate script, open into vaults holding mummified remains — but not from any human.

Inside, the treated cadavers of long-dead baboons sit up in these niches, animals once thought to have a rare connection with Egyptian deities. A pair of stone steps sits underneath the windows, while large-cone-like pillars framing the steps are flattened off at the top for offerings.

While these tombs were built late in ancient Egypt’s long history, a period that represented huge changes in governance and society, the representation of baboons had remained consistent ever since the beginnings of complex civilization in the Nile Valley.

The reasons these animals were regarded as sacred, however, is deeply rooted in ancient Egyptian religion and culture.

Why Did the Egyptians Think Baboons Were Sacred?

The sacred baboon was a recurring theme in ancient Egyptian art and religion. These depictions ranged from predynastic statues to wall paintings, amulets, and statues — a tradition spanning 3,000 years. Sometimes, in these renditions, the baboons are shown wearing a circular lunar disk.

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“Baboons are regularly associated with the moon,” says Nathaniel Dominy, an anthropologist at Dartmouth College who has studied baboons in ancient Egypt. In other renditions, they are shown facing the sun with raised arms. “It’s known as the posture of adoration.”

Some researchers think that the Egyptians believed the baboons had a special way to communicate with the sun god, Ra, and the moon good Thoth. It’s possible that ancient Egyptians revered baboons after observing the way they communicate, leading them to infer the animals’ ability to commune with these gods.

“The baboon vocalizations were much more human-like than anything from other animals,” says Dominy. “They would have resonated with [Egyptians] extremely strongly.”

When Did Egyptians Start Revering Baboons?

The burial of baboons in tombs dates back to the predynastic period. As early as 3,500 B.C.E, baboons were mummified and buried in the sand. Researchers have also discovered the remains of these baboons, where they were well-preserved due to the region’s dry conditions.

It wasn’t just a few, either — it appears that many of the animals were imported to an area just south of Luxor, known as Hierakonpolis. These remains were found alongside those of cats, elephants, and other exotic animals. “It looks, for all intents and purposes, like a zoo,” Dominy says.

Over a period of 3,000 years, baboons were nearly always depicted in the same way — sitting down with their hands placed on their knees, often with protruding genitals. One of the early depictions of baboons dates back to the first dynasty, a small statue known as the Narmer baboon.

How Were Baboons Depicted in Ancient Egypt?

In almost all cases, these depictions show what appear to be a species of baboon known as Papio hamadryas, large monkeys with a dog-like muzzle. Interestingly, physical remains discovered in burials or mummifications are a mixture of olive (Papio anubis) and hamadryas baboons.

It’s unclear whether this bias in depiction reveals that the Egyptians favored the hamadryas species more than the olive baboon. It’s also possible that hamadryas baboons were more available at certain times due to trade politics, despite their natural range coming from farther regions of Egypt. At some point, that may have led to them becoming the standard species portrayed in art.

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Finally, it’s possible that it’s all about the mojo. Hamadryas baboons typically have larger genitals than olive baboons, which seems to be significant, says Dominy, given their prominent display in artistic depictions.

The mummified baboons tend to appear similar to the way the animals are depicted in artwork and artifacts: With the cadavers usually placed in a sitting position, the monkey’s tail wrapped to the right.

Did Other Cultures Revere Baboons?

Many other cultures in sub-Saharan Africa don’t always take a favorable view of baboons, due to their penchant for crop raiding. This makes it all the more curious that the Egyptians did hold them in high esteem — at least symbolically.

“Baboons have this reputation for just being malicious [in sub-Saharan Africa],” Dominy says.

It’s unclear why, but Dominy speculates that the Egyptians took a different view of the primates due to the ancient pastoral ancestry of many of the people who eventually settled in the Nile Valley. While baboons may raid the crops of sedentary farmers, they typically don’t cause problems among semi-nomadic pastoralists, who might keep goats and cattle for sustenance.

Some of these pastoralists eventually settled in oases along the Nile River, but these areas were outside the natural ranges of olive or hamadryas baboons. “[The pre-dynastic Egyptians] were never farmers at a time when they were coexisting with baboons,” Dominy says.

At some point, though, these people would have noticed their behavior. Baboons will sometimes chatter at the moon, or at the sun at dawn. Dominy says that some Egyptologists have speculated that this is why baboons were often depicted alongside the moon or sun.

Did Ancient Egyptians Treat Baboons Poorly?

While they likely held a sacred function for ancient Egyptians, that doesn’t mean that baboons were literally worshipped: In fact, they were essentially raised in captivity before being mummified.

What’s more, some of the evidence from buried baboons revealed they had sustained numerous injuries on their forearms — right about where they would be struck while protecting their heads or bodies from physical attacks. A study published in PLOS ONE in 2023 revealed that the captive conditions for many of the animals were less than comfortable.

Of the remains of at least 36 baboons the researchers examined, only four looked healthy, with all others showing deformities. “They often had bent limbs, typical of rickets caused by a lack of vitamin D due to insufficient sunlight,” says Wim Van Neer, one of the study’s authors and an archaeozoologist from the Institute of Natural Sciences in Belgium, in a press release

Some baboons were kept by royal families or other prestigious members of society. But others were likely kept for profit by priests, Dominy says. Once they died, their cadavers would have been sold to people looking to mummify the primates to present them as offerings to the gods, similar to cats, and other animals.

“They were utilitarian animals to illustrate power and prestige,” adds Dominy.

The practice was put to an end at the close of the Ptolemaic dynasty, when Christians began destroying pagan symbols. North Saqqara, where many baboon remains have been found, was destroyed by the late 8th century C.E., putting the final nail in the proverbial coffin of mummified, sacred baboons.

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