Codex Xolotl

The Codex Xolotl (also known as Codicé Xolotl) is a postconquest cartographic Aztec codex, thought to have originated before 1542. It is annotated in Nahuatl and details the preconquest history of the Valley of Mexico, and Texcoco in particular, from the arrival of the Chichimeca under the king Xolotl in the year 5 Flint (1224) to the Tepanec War in 1427.
The codex describes Xolotl's and the Chichimeca's entry to the then unpopulated valley as peaceful. Although this picture is confirmed by the Texcocan historian Fernando de Alva Cortés Ixtlilxochitl (1568 or 1580–1648), there is other evidence that suggests that the area was inhabited by the Toltecs.
Ixtlilxochitl, a direct descendant of Ixtlilxochitl I and Ixtlilxochitl II, based much of his writings on the documents which he most probably obtained from relatives in Texcoco or Teotihuacan. The codex was first brought to Europe in 1840 by the French scientist Joseph Marius Alexis Aubin, and is currently held by the Bibliothèque nationale de France in Paris.
The manuscript consists of six "amatl" boards measuring , with ten pages and three fragments from one or more pages. While it is unknown who did the binding of the manuscript, it is cast like a European book back to back. The Codex Xolotl has been an important source in giving detailed information on material, social, political and cultural changes in the region during the period. It is one of the few still surviving cartographic histories from the Valley of Mexico and one of the earliest of its type.
Historical Significance.
The Codex Xolotl is an example of material culture. This means that the codex can be used as an object to understand the culture of the Aztecs. The object itself shows the Aztec understanding of the history of Texcoco. It is also a document that includes an early instance of Nahuatl writings referencing specific dates. There is some ongoing debate regarding how many writers were involved in creating the codex itself. This can propose discrepancy about how much personal influence was involved in creating the document.
Controversy.
There are some debates that question how valid the codex is from an archaeological perspective. This debate roots itself in the work of Jeffrey Parsons in 1970s, with his book detailing the archaeology of the Texcoco region. One side of this debate states that the codex itself is not supported by the archaeological evidence of the region.
Another argument claims that within the discrepancies, some historical facts can be separated from the mythology. An alternate response to Parsons' argument uses a hypothesis regarding a conflict between the Tula and Cholula regions to support Parsons' position.