He wrote on the history of Mexico and other neighboring nations in the Nahuatl and Spanish languages. The most important of his surviving works is the Relaciones or Anales. This Nahuatl work was compiled in the early seventeenth century, and is based on testimony from indigenous people.
He chronicled Mexico's history and that of neighboring regions in both Nahuatl and Spanish. One of his enduring contributions is the Relaciones or Anales. This Nahuatl text was assembled in the early 17th century, based on testimonies from indigenous people.