Mesoamerican populations left numerous written traces in the form of paintings or engravings present in codices, on steles and on temple walls. Among the Aztecs, books were very numerous and preserved in special libraries. The oldest evidence of a form of writing in Mesoamerica dates back to the Olmec civilization in the form of calendar glyphs. The codices are pictorial documents produced in the Maya, Aztec, Mixtec and Zapotec civilizations which were made mostly but not only in central Mexico. We find, listed in the codices, scientific knowledge and cultural practices of these different civilizations concerning religious beliefs, rites and ceremonies, history, genealogies of kings, geographical notions, the economic system, the chronology and many other subjects. The main sources of information we have concerning the Maya and Aztec civilizations, include the Mixtec codices, the Borgia group contributions and the four Maya manuscripts that survived to the destruction. Numerous codices are described in the text. Much information concerning the history and culture of these two peoples is also due to chroniclers and historians, whether before or after the Spanish conquest. The life and historical contributions of the most famous of them are described in this chapter. During the early period of Spanish colonization, brutal means were used by evangelizers to extirpate indigenous beliefs, including the destruction by autos-da-fé of writings that were considered by the Spanish authorities to be “demonic books.”