The 16th century conquistador Hernán Cortés led Spanish troops into the Valley of Mexico in search of Aztec gold. His actions in the New World are widely seen by historians to have dramatically altered Mesoamerican history.
Cortés's ships landed in Veracruz in 1519. He was welcomed into the Aztec capital, Tenochtitlán, by its monarch, Moctezuma. Cortés learned of Moctezuma's inheritance and in 1520, arrested him and seized it. Gold only figured partially into the total inheritance, which was also comprised of pots, art objects, jewels and clothing.
Cortés's actions initiated the ethno-environmental conflict that has occurred between the ethnic groups of Mexico for the 500 years following. According to Stuart Matthews' case study, ethno-environmental conflict "refers to an ongoing state of hostility between two groups. ... often, but not always, involving violence." It is in this sense that Cortés's search for gold permanently changed Mexican history.