Researchers Discover a New Reason Why Ancient Societies Practiced Human Sacrifice

Ritualized killings once took place in many societies and in most regions around the globe. 


Human sacrifice is today, a part of urban legends or the serial murders of a few, craven madmen. But dig deeper into history and you’ll find that it was a part of many societies and took place in most regions around the world. These include the South Pacific, ancient Japan, early Southeast Asian societies, ancient Europe, certain Native American cultures, in Mesoamerica, and among the great civilizations of the ancient world. Babylon, Egypt, China, Greece, and even the precursor to the Romans, all took part in ritualized killings. In ancient Egypt and China, for instance, slaves were often buried alive, along with the body of their sovereign, to serve him in the afterlife.

Though condemned by the international community and wiped off the face of the Earth (as far as we know), the idea of human sacrifice still sends chills up the spine. Perhaps it’s because it runs counter to all we hold dear. Human rights are supposed to be edified, though in many places in the world, only lip service is paid. But even that small effort shows how the concept has solidified within the international psyche.

We’re told that in humanity’s ancient past, this macabre practice was performed to placate certain gods. But what if that was merely the justification fed to the masses? What if in actuality, it had a political purpose? A fascinating study published in the journal Nature, finds that ritual human sacrifice may have been a part of more sinister designs.  

Here, scientists employed the “social control hypothesis,” to suggest that elites used ceremonial killings to consolidate power. By being the conduit to the divine, and elucidating what the gods wanted, emperors, priests, and others of high social stature, legitimized their power in the minds of the people, elevated themselves, and installed a silencing fear among those who would obstruct them. Psychologist Joseph Watts and his team found evidence supporting this hypothesis. He’s a doctoral student of cultural evolution at the University of Auckland in New Zealand. His team collaborated with colleagues from Victoria University, also in New Zealand.

Capt. James Cook Witnesses human sacrifice in Tahiti. [Public domain], via Wikimedia Commons

Researchers evaluated 93 Austronesian cultures, a seafaring people (and language family) originating in Taiwan, who came to populate parts of ancient Australia, Southeast Asia, and Polynesia. Over time, their societies differentiated dramatically. 40 distinct breakoffs were found to practice human sacrifice at some point in the distant past. Watts and colleagues wanted to know what, if any effect, ritualized killings had on the societal makeup, particularly in terms of social stratification and class structure. Researchers separated these societies into three groups: egalitarian, moderately stratified, and highly stratified. They evaluated each depending on with what ease social mobility took place and how rigid the social hierarchy was.

Watts and colleagues found anecdotal evidence that human sacrifice was a power grab, and a way to maintain social control. Researchers employed a technique called phylogenetic analysis in the study. This is usually used to follow the twists and turns of evolution in a species. Sociologists adopted the technique to study language development. Here, it was used to plot relationships among the different cultures being studied. This helped recognize whether certain traits in one culture were present in another, and determine what relationship human sacrifice might have on social stratification.

Data was derived from historical and ethnographic records. Though the methods differed and a variety of reasons were used to justify the heinous act, the results were always the same, the solidification of power. What’s more, victims tended to be the same, someone of low social status, such as a slave or prisoner of war. Phylogenetic analysis showed that human sacrifice started in egalitarian societies, but after it was introduced, these tended to become social hierarchies. Once in place, ritualized killings helped leaders assume greater control.

Aztec Sacrifice 16th century, from the Codex Magliabechiano. Via Wikipedia Commons 

Two-thirds of highly stratified societies once took part in the grisly act, while only a quarter of egalitarian cultures did. The groups who at one time practiced human sacrifice, had more rigid castes, titles that were inherited, and less social mobility. Researchers concluded that “ritual killings helped humans transition from the small egalitarian groups of our ancestors and the large, stratified societies we live in today.” Though sociologists have posited such a hypothesis before, this is the first time it’s been scientifically studied.

Among many today, religion is thought to be the standard bearer of morality. Yet, this study, as Watts said, “…shows how religion can be exploited by social elites to their own benefit.” Since these societies prospered, it proved an effective method of social control. “The terror and spectacle [of the act] was maximized,” in order to achieve the desired effect, Watts told Science. Moreover, ritualized killings would’ve given pause to rivals considering a power play for the throne, foreign ministers mulling over war, and bands among the populace grumbling for rebellion.

Yet, Watts and colleagues posit that social cohesion and stratification was necessary to give humans the ability to develop large-scale agriculture, build cities, erect monumental architecture and public works projects, and to allow for greater capacities for science, art, and learning. Though these findings are thought provoking and significant, some experts wonder if the phylogenetic analysis proves a causal relationship, or merely hints at one. Also, ritual sacrifice is probably not the only reason societies grew hierarchical and complex. Similar hierarchies to those erected in the ancient days, are still present in many of these societies, Watts said, though modern religions have done away with the practice which helped to established them.

To learn the details of one of the most famous cases, an Aztec human sacrifice, click here: 

Why a great education means engaging with controversy

Jonathan Zimmerman explains why teachers should invite, not censor, tough classroom debates.

Sponsored by the Institute for Humane Studies
  • During times of war or national crisis in the U.S., school boards and officials are much more wary about allowing teachers and kids to say what they think.
  • If our teachers avoid controversial questions in the classroom, kids won't get the experience they need to know how to engage with difficult questions and with criticism.
  • Jonathan Zimmerman argues that controversial issues should be taught in schools as they naturally arise. Otherwise kids will learn from TV news what politics looks like – which is more often a rant than a healthy debate.
Keep reading Show less

Are these 100 people killing the planet?

Controversial map names CEOs of 100 companies producing 71 percent of the world's greenhouse gas emissions.

Image: Jordan Engel, reused via Decolonial Media License 0.1
Strange Maps
  • Just 100 companies produce 71 percent of the world's greenhouse gases.
  • This map lists their names and locations, and their CEOs.
  • The climate crisis may be too complex for these 100 people to solve, but naming and shaming them is a good start.
Keep reading Show less

SpaceX catches Falcon Heavy nosecone with net-outfitted boat

It marks another milestone in SpaceX's long-standing effort to make spaceflight cheaper.

Technology & Innovation
  • SpaceX launched Falcon Heavy into space early Tuesday morning.
  • A part of its nosecone – known as a fairing – descended back to Earth using special parachutes.
  • A net-outfitted boat in the Atlantic Ocean successfully caught the reusable fairing, likely saving the company millions of dollars.
Keep reading Show less