Bernardino de Sahagún was a Franciscan friar, missionary priest and pioneering ethnographer who participated in the Catholic evangelization of colonial New Spain. Born in Sahagún, Spain, in 1499, he journeyed to New Spain in 1529. He learned Nahuatl and spent more than 50 years in the study of Aztec beliefs, culture and history. Though he was primarily devoted to his missionary task, his extraordinary work documenting indigenous worldview and culture has earned him the title as “the first anthropologist." He also contributed to the description of Nahuatl, the imperial language of the Aztec Empire. He translated the Psalms, the Gospels, and a catechism into Nahuatl.

Nahuatl, Aztec, or Mexicano is a language or, by some definitions, a group of languages of the Uto-Aztecan language family. Varieties of Nahuatl are spoken by about 1.7 million Nahua peoples, most of whom live mainly in Central Mexico and have smaller populations in the United States.