The Aztecs were nomadic tribes who lived in Northern Mexico between 13th century and 15th century, until the Spanish invaded and conquered them in 1521. Aside from being known for their advanced agriculture and irrigation techniques, their writing, calendar and pyramids, the Aztecs are also known for mass human sacrifice.
Some historians estimate that Aztecs sacrificed about 20,000 people a year to their idols. Others believe that the number is exaggerated but there is no doubt that human and animal sacrifice was an important ritual for the Aztecs. As per their belief, Aztecs thought that deities required blood and so to keep the deities' needs quenched and to also avert misfortunes and natural disasters, Aztecs engaged in periodic human sacrifice. This involved sacrificing of volunteers or captives. Some people also engaged in "blood letting." The first Spanish invaders witnessed some of the horrific rituals which involved removing the beating hearts of people and offering them to deities at temples.
Aztecs also engaged in cannibalism, they sometimes consumed humans after sacrifice. An anthropologist, Michael Harner, theorized in 1977 that Aztecs may have engaged in cannibalism due to a scarcity of protein sources in that region at the time. Other experts believe that human sacrifice and cannibalism were only for ritualistic purposes. The strange traditions of Aztecs continue to be a popular topic for research and discussion.
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