Answer:
Hernán Cortés de Monroy y Pizarro, 1st Marquis of the Valley of Oaxaca, born circa 1485, died December 2, 1547, was a Spanish Conquistador who led an expedition that caused the fall of the Aztec Empire and brought large portions of mainland Mexico under the rule of Spain.
Principally, he destroyed the Aztec Empire and conquered what is today Mexico.