In what three major ways did Religion shape the Aztec Empire?
My thesis is that the Aztecs Empire was an empire that was shaped by religion. I have two points: Daily life and War... but if those are bad you can disregard them.
You have a good basis for your essay. Your answer will undoubtedly examine the religious ideology that drove human sacrifice in Aztec society. The Aztec world view believed that the earth passed through cycles of creation and destruction. Humans existed in a world that was therefore facing inevitable destruction. The only thing that could possibly forestall this destruction was regular offerings of human blood to nourish the gods. If these offerings were not made, it was thought that the sun would not rise and continue to sustain human life. Interestingly all people engaged in this process through self-laceration - so not just through human sacrifice.
Clearly, then, religion and Aztec warfare were closely linked, with the Aztec empire stretching outwards as they brought back more slaves to sacrifice. Try to see the film Apocalypto, if you haven't already - a brilliant story based on these times.
Another aspect you will want to examine is the Aztec understanding of astronomy and how they used it to create a calendar and how it influenced the building of religious temples - two ways in which the Aztec empire were well ahead of their time.
Accessteacher has given you a great start for your essay.
I encourage you to look at the agricultural practice of growing corn as the main crop. Corn is a very heavy feeder and is only productive on an area of land for very few years. The Aztecs did not use plows or metal tools, fertilizer such as we know it. So, they were continually in search of new land on which to grow their crops. This created a need to conquer or make war. It created a greater increasing need for sacrifical victims to ensure a good crop of corn (maize).
Several of the Aztec religious practices involved the growth of the corn, harvest and rain. All of these religious practices involved blood-letting in some form, human sacrifice, and child sacrifice.
The Aztec calendar evolved from earlier civilizations as a way to plan the sacrifices as well as a planting calendar.
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