Q&A: Why and how did the Aztecs practise human sacrifice?

Q: Why did human sacrifice take place in the Aztec empire, and how often?

A: Frustratingly, it's quite hard to tell how much sacrifice there was. Depending on which sources or which set of statistics you use, you can either end up with a number that is a very high or really quite low. It’s safe to say though that there was prominent and regular human sacrifice taking place.

The root of this, as far as we can tell, is to do with a reciprocal relationship between the gods and humans. The Aztecs believed that you had to give back to the gods because they gave to you.

It’s safe to say that there was prominent and regular human sacrifice taking place

The mythical histories of the Aztec people talk about the gods sacrificing themselves to create humanity. Take the account of the great earth crocodile Tlaltecuhtli. She was supposedly ripped in half to create the land, and then humans had to feed her with blood in order to sustain her and pay back the original debt.

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In another account, one god goes into the underworld and steals the bones of a man and a woman from a previous era from under the nose of the 'Lord of the Land of the Dead’. He brings the bones to a place that broadly translates as ‘paradise’, where they are ground up by a female god on a grinding stone and turned into a sort of bone flour. Then the male gods let blood from their penises to moisten the dough in order to form little human figures out of it. The Aztecs believed that up to this point there had been five ages of the world and that they were living in the fifth age, and that is how this incarnation of humanity came to be.

Human sacrifice was intended to pay back the debt that was formed when the gods let blood from themselves to create the world. The Aztecs believed that if they didn’t sustain the sun with blood, the world would come to an end. It was kind of like feeding the gods. Unlike in some other sacrificial cultures, where you might offer a human sacrifice to gain the power of a person – become richer or more important or have more children – for the Aztecs, human sacrifice wasn't really for personal gain. Essentially, it was an altruistic act – human sacrifice was necessary for all of humanity. This was a communal response to a collective debt.

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Q: Who were the victims of sacrifice? Is it true that people willingly volunteered?

A: In theory, there were some voluntary victims of human sacrifice. In reality, it's very hard to tell whether this was the case. The majority of victims were people (mostly men, but sometimes women and children) captured in war. Some of them were sacrificed as generic victims – if they needed to sacrifice say five people. Some were sacrificed as impersonators of the gods, known as ixiptla; they took on the mantle of a god and were killed in honour of the gods they were impersonating. These ixiptla formed a prominent part of the regular festivals.

We know that if you were born with a double cowlick – those flicks that make your hair go going the wrong direction – then you were destined to become a sacrificial victim

Children were sacrificed in particular for Tlaloc, the rain god. These children were mostly from within the Aztec group – they came from Tenochtitlan, the ancient capital of the Aztec empire. We know that if you were born with a double cowlick – those flicks that make your hair go in the wrong direction – then you were destined to become a sacrificial victim.

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There is some talk about whether if, when a child like this was born, especially in a culture with a high infant-mortality rate, you might have been able to kind of mentally distance from them. But we also know that sacrifice was based on a sympathetic magic. The children were supposed to cry, and people were supposed to cry about them dying. These tears would bring the rain.

For me, it's very notable that the children offered to Tlaloc were not killed in the city, but were instead taken into the mountains to be sacrificed in a lake. It’s significant that the one sacrifice that very prominently took place away from the city is that of Aztec children. You wonder whether people would have been prepared to watch that spectacle in quite the same way.

It's very notable that those children were not sacrificed in the city, but were taken into the mountains to be sacrificed in a lake

We mustn't forget that other cities around Tenochtitlan were also practising sacrifice. There was an acceptance that as a warrior, if you were captured by another city, you could be sacrificed.

It was a shared belief that dying as a sacrifice or in battle was one of the very few ways you could get a privileged afterlife. The closest parallel is something like martyrdom, where you die for the gods and gain a privilege as a result. The vast majority of people were destined for a place called Mictlan after they died, which is not exactly hell, but is a nonetheless dark, damp and unpleasant place, where you would have to endure low-grade suffering for eternity.

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But if you were a man who died in sacrifice, first you would accompany the sun for four years, leading and heralding the gods in a glorious way. Then, you would go off to become a hummingbird or a butterfly that dances in the sun and sips nectar. The sources suggest that in paradise, you would live drunk, oblivious to the cares of the world. You can see why that might seem an appealing option.

In reality, the likelihood is that while some people faced the prospect of being sacrificed by exalting their cities, praising the gods and bravely accepting their fate as a warrior, other people were dragged kicking and screaming.

Caroline Dodds Pennock is lecturer in international history at the University of Sheffield, and author of Bonds of Blood: Gender, Lifecycle and Sacrifice in Aztec Culture (Palgrave Macmillan, paperback edition, 2008).

Read more by Caroline Dodds Pennock: 'Mass murder or religious homicide? Rethinking human sacrifice and interpersonal violence in Aztec society'