As a general rule, the more you learn about history, historical methodology, and historiography, the more you learn to distrust the claims of groups and people that tend to hang out on the fringes of culture and society and the historiography they present. This goes for all along the spectrum of human politics, ideology, religion, and identity. This includes Holocaust Denialism, "Stalin weren't so bad", "Everything is America's Fault", Black Cleopatra, Best Korea, Chartists, Lost Causers, etc.

In the particular case of Aztec human sacrifice, we are seeing a revisionism that attempts to paint Native peoples as being pure angels that have been corrupted and mis-represented by the "evil white man". Interestingly, this is an internalization of the Noble Savage, mythology of Europeans and White Americans in the 18th and early 19th Century. In this regard, its not so much that the "Noble Savage" was free of the class and moral restrictions of Western society as well as living in perfect harmony. This newer mythology that is closely related to extreme fringes(so extreme that Leonard Peltier and Ceasar Chavez would think them out there), of Chicano and Native American movements reinvents it in its own image. In their interpretations, NA's didn't go to war against each other, didn't damage the environment, didn't have issues of violence, race, intolerance, and possibly sacrifice each other to their respective god, instead the white man came along and ruined their perfect lives.

Well, sorry, it just doesn't pan out that way.

A fantastic example of how this is not true, is the evidence of mass killings that aren't human sacrifice related, but are warfare related such as the Crow Creek site in South Dakota. Here almost 500 villagers appear to have been surrounded, starved, and then massacred in the early 14th Century, or almost 200 years before Christopher Columbus set foot on a single Caribbean island. This is just one example of inter-tribal violence before the arrival of white men.

Now, having demonstrated that, let's look at the arguments that the Conquistadors lied. Firstly, human sacrifice has been seen all over the world and throughout history in Europe, Africa, Asia, the Pacific, and so it's odd to think that somehow it may have skipped the Americas. It's odd to think because there is direct proof it did not. While the Aztec codices are largely recreated by Latin priests taking dictation from older Aztecs in an attempt to reconstruct them after they were widely destroyed early after the conquest, we do have surviving examples of Mayan codex such as the Madrid Codex, which demonstrates examples of human ritual sacrifice. What's interesting, is that in this codex, you can see the same stones the victims would be stretched over and have their heart cut out from.

Well, that's still not the Aztec though, right? Here's the problem, the archaeology doesn't pan out. In this L.A. Times, they talk about the evidence for the sacrificial methods that didn't involve hauling them up to the top of a temple. They found evidence for the practices of burning people alive, organ storage, etc. There is also proof, of earlier Meso-American tribes using the practice. There is evidence of canibalism, found at the Great Temple in Tenochtitlan, as well. There is evidence of trophy taking available, evidence that Spaniards, even fell victim to them.

The evidence is overwhelming that Aztecs did practice ritual sacrifice and cannibalism. To refute it is to refute the very practice of forensic science and archaeology.

HOWEVER......

The story's of the massive sacrifices such as those carried out in the 1487 Temple re-dedication, seem to fall apart upon further study. The links provided above offer evidence of that and where archaeologists talk about it. It does seem rather outlandish that as many as 80,000 people in four days were sacrificed by hand. The Nazis could have easily done that many with their industrialization, but it does seem impossible for an early Bronze-Age level civilization to kill that many and evidence seems to support that. However, the evidence offered shows that there were massive sacrifices though the number was more in the range of 5,000 to 10,000 people.

Now, some revisionists would take that and say, "SEE!!!! LIES!!!! WHAT ELSE ARE THEY LYING ABOUT?!?!!?!" And that's the problem. When evidence doesn't exist that original accounts are true, it becomes easy to dismiss the entire premise, or to start coming up with radical interpretations of evidence not consistent with confirmable, reliable facts. It falls into the realm of "The Egyptians Knew How To Fly!!!" because they made a potential wooden glider. Yeah, so what? Doesn't mean they know how to fly. Every civilization that ever made arrows had a crude understanding of aerodynamics as evidenced by fletching. Hell, returning boomerangs have been used in Australia for about ten thousand years, and we even have some found in Europe made from mammoth tusk. Though, no one seems to claim that Australian Aborigines, who knew how to make functional wings apparently also could make gliders or even airplanes. That's because there's no ideological drive to make that connection.