Colonial Mexico refers to the period from 1521 to 1821 when Mexico was part of the Spanish Empire. After the fall of the Aztec Empire, Spanish conquistadors, led by Hernán Cortés, established control over the region. The Spanish introduced their language, culture, and religion, significantly impacting the indigenous populations. During this time, Mexico became a vital part of the Spanish colonial economy, primarily through mining and agriculture. The establishment of cities, such as Mexico City, and the spread of Catholicism were key features of colonial life. The period ended with the Mexican War of Independence, leading to Mexico's sovereignty.