Why do historians know a great deal about the Aztecs?

Historians know a great deal about the Aztecs due to a combination of extensive archaeological findings and the detailed accounts left by Spanish conquistadors and missionaries, such as Hernán Cortés and Bernardino de Sahagún. These sources provide insights into Aztec society, culture, religion, and governance. Additionally, the Aztecs developed a rich written tradition using pictographs and codices, which further contribute to our understanding of their civilization. The combination of these sources allows historians to piece together a comprehensive picture of the Aztec Empire before its fall in the early 16th century.