What happened when Hernán Cortés arrived in the territory of the Aztec Empire

The Spanish conquest of the Aztec Empire, also known as the Conquest of Mexico (1519–21),[6] was one of the primary events in the Spanish colonization of the Americas. There are multiple 16th-century narratives of the events by Spanish conquerors, their indigenous allies, and the defeated Aztecs. It was not solely a contest between a small contingent of Spaniards defeating the Aztec Empire but rather the creation of a coalition of Spanish invaders with tributaries to the Aztecs, and most especially the Aztecs' indigenous enemies and rivals. They combined forces to defeat the Mexica of Tenochtitlan over a two-year period. For the Spanish, the expedition to Mexico was part of a project of Spanish colonization of the New World after twenty-five years of permanent Spanish settlement and further exploration in the Caribbean.

the western roman empire flourished, but the eastern portion of the empire struggled.

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