Question

The fall of Tenochtitlán in 1521 was significant because

Answer 1

It was a major step in the big cultural ( and ethnic and religious) shift in the Americas: From the Indigenous cultures to European ones. The Aztecs and the Incas were the only empires strong enought to stand a chance against the conquerors, and when  they failed, the whole continent basically "stood open" for the colonizers, who would then encounter only limited resistance.
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