"Crónica X" is the name given by Mesoamerica

Mesoamerica

Mesoamerica is a region and culture area in the Americas, extending approximately from central Mexico to Belize, Guatemala, El Salvador, Honduras, Nicaragua, and Costa Rica, within which a number of pre-Columbian societies flourished before the Spanish colonization of the Americas in the 15th and...

n researchers to a postulated primary-source early 16th century historical work on the traditional history of the Aztec

Aztec

The Aztec people were certain ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl language and who dominated large parts of Mesoamerica in the 14th, 15th and 16th centuries, a period referred to as the late post-classic period in Mesoamerican chronology.Aztec is the...

 and other central Mexican

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

 peoples, which some researchers theorize formed the basis for several other extant 16th century documents. The chronicle's author is unknown and the work has been lost, if indeed it ever existed, but it is thought to have been used as a source for several other chronicles that contain striking similarities among these the Chronicles of Fray Diego Durán

Diego Durán

Diego Durán was a Dominican friar best known for his authorship of one of the earliest Western books on the history and culture of the Aztecs, The History of the Indies of New Spain, a book that was much criticized in his lifetime for helping the "heathen" maintain their culture.Also known as the...

, Juan de Tovar and Jose de Acosta

José de Acosta

José de Acosta was a Spanish 16th-century Jesuit missionary and naturalist in Latin America.-Life:...

.

The similarities between the materials and scope of documents such as the Durán, Tovar and Acosta codices

Mesoamerican literature

The traditions of indigenous Mesoamerican literature extend back to the oldest-attested forms of early writing in the Mesoamerican region, which date from around the mid-1st millennium BCE. Many of the pre-Columbian cultures of Mesoamerica are known to have been literate societies, who produced a...

were first noted by Robert Barlow in 1945, which led him to postulate that they all must have had a particular source in common, which he denoted as Crónica X.