Huitzilopochtli was a tribal god and a legendary wizard of the Aztecs. Originally he was of little importance to the Nahuas, but after the rise of the Aztecs, Tlacaelel reformed their religion and put Huitzilopochtli at the same level as Quetzalcoatl, Tlaloc, and Tezcatlipoca, making him a solar god. Through this, Huitzilopochtli replaced Nanahuatzin, the solar god from the Nahua legend. Huitzilopochtli was said to be in a constant struggle with the darkness and required nourishment in the form of sacrifices to ensure the sun would survive the cycle of 52 years, which was the basis of many Mesoamerican myths. While popular accounts claim it was necessary to have a daily sacrifice[citation needed], sacrifices were only done on festive days. There were 18 especially holy festive days, and only one of them was dedicated to Huitzilopochtli.
Every 52 years, the Nahuas feared the world would end as the other four creations of their legends had. Under Tlacaelel, Aztecs believed that they could give strength to Huitzilopochtli with human blood and thereby postpone the end of the world, at least for another 52 years.
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{K:163889} 4/21/2009