Spanish conquistadores led by Hernán Cortés conquered the Aztec capital of Tenochtitlan (on the site of present-day Mexico City) in 1521, and Franciscan missionaries followed shortly thereafter in 1524. Sahagún was not in this first group of twelve friars, which arrived in New Spain in 1524. An account, in both Spanish and Nahúatl, of the disputation that these Franciscan friars held in Tenochtitlan soon after their arrival was made by Sahagún in 1564, in order to provide a model for future missionaries. Thanks to his own academic and religious reputation, Sahagún was recruited in 1529 to join the missionary effort in New Spain. He would spend the next 61 years there.