I'm not well acquainted with the history of mesoamerica. My understanding is that the narrative is sacrifice would bring good fortune.
Having thought about human sacrifice, the political scientist in me is seeing a tyrannical state controlling its people.
Is it possible these practices had less to do with bringing rain and more to do with control?
Was human sacrifice a terror tactic? Or a religious rite? I’m going to go with the second one, at least in most cases. This doesn’t mean that religious rituals did not have political implications, just that they were not a weapon of terror, except in a few unusual circumstances. Just a quick note, I’m going to be working from the Mexica perspective, because this is who people usually have in mind when discussing this topic, and because it is where we have the more detailed sources.
The first point we need to acknowledge is that when people talk about human sacrifice, they are really looking only at a small part of a much larger ritual. In reality, these ceremonies often spanned multiple days, and involved many innocuous ritual acts such as: dancing, singing, feasting, drinking, picking flowers, hanging paper effigies in trees, scattering seeds, undertaking processions, fasting, burning incense, burying offerings, auto-sacrifice, and animal sacrifice. In many cases the sacrifice of human beings was not the end of the ritual, or even necessarily its climax. Some rituals even lacked a human sacrifice altogether.
In Etzalcualiztli, priests even dressed in bird costumes and went into shallow water to quack and act like ducks. In the same ritual, they undertook a sacred procession. If they ran into anyone on the road, the priest beat them and stole their goods. This included the Huey Tlatoani’s tax officers! Other rituals could be just as elaborate. In at least one, priests and warriors undertook mock battles in which they attempted to steal each other’s treasure (it was returned later). In Ochpaniztli there was even a mock battle fought in the streets of Tenochtitlan! The longest and most complex of these was probably Toxcatl. This festival was in preparation for over a year. The ixiptla (god impersonator) of Tezcatlipoca lived a year as the god, leading ceremonies, playing music, and advising the government, before being sacrificed.
If the goal of human sacrifice was to spread terror, then why go to the trouble and expense of hosting such diverse activities? Why not just kill people? The problem here is that human sacrifice is often viewed in isolation, removed from its religious context. This leads to the impression that human sacrifice was Mexica religion. This is ridiculous of course. It would be like saying the core tenant of Christianity was blood libel.
If terror was not the point, then what was? Each ritual act had significance of course. The aim of many acts was to restore fertility to the earth. Things like, spreading seeds, making bird calls, and making offerings. There is yet more significance in the structure of rituals. Note that most involve a lot of public participation, and this brings me to the political aspect. Most Mesoamerican communities were heterogeneous, and populations mixed quite freely with each other. In order to build a collective identity these diverse origins, rituals were used to create a common, collective, experience.
The rituals also legitimized the social structure. The priests and nobles who led their ceremonies justified their positions by presenting themselves as bringers of fertility to these communities. The Mexica took this to the next level, by using rituals to claim legitimate and divinely sanctioned authority over all of Central Mexico, not just their own core altepetl. I think this better explains some of their political acts than as a terror tactic. For example, the Mexica invited their enemies, the Tlaxcalans, to witness some large ceremonies. Traditionally, this has been interpreted as a kind of intimidation. I think this is a reductive interpretation. Instead, this was an opportunity for networking. Although politically distinct, culturally the Tlaxcallans and Mexica were almost identical, and so it may have been possible to ‘seduce’ or bribe individual lords to come over to the Mexica’s side. Furthermore, by merely showing up, the Tlaxcalans were basically admitting to Mexica supremacy over Central Mexico.
So, where is the exception? It comes during the final Siege of Tenochtitlan. The Mexica captured a number of Spaniards during the many street battles. The Mexica knew of the Spaniards dread of human sacrifice, and so deliberately sacrificed these captured Spaniards in full view of their comrades. This is the one point where we can say that sacrifice was used as a terror weapon. However, it is also worth pointing out that this was an unusual circumstance, and not typical of Mexica religious practices or even norms of warfare.
I could go into far more detail on any of these points. But I think you get the idea.
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