Ms. manuscript in the form of a circular sheet calendar.

This Aztec pictorial calendar wheel, commonly known as the Boban calendar wheel, is printed on amatl (fig bark) paper. Initially dated to approximately 1530 by Doutrelaine, 1538 by John B. Glass and Donald Robertson in the Handbook of Middle American Indians, it has now been more accurately dated to 1545 or 1546. The initial dating of 1530 derives from the identification of two figures shown in the document: one in the upper left is said to be Hernán Cortés and the upper right figure is said to be don Antonio Pimentel, depicted as the son of Ixtilxochitl. Patricia Lopes Don argues for the compilation date of 1545-1546 based on the fact that don Antonio Pimentel Tlahuitoltzin was the ruler of Texoco de Mora from 1540-1546. The additional suggested date of 1538 can be traced to the Nahuatl notation of the year 7 Rabbit in the upper right hand corner but it still prior to Pimentel's rule.

The outside ring of the calendar is comprised of glyphs for the eighteen months of twenty days, or veintenas, which make up the Aztec calendar. This outside ring surrounds a central three part history with three pairs of figures and glosses in Nahuatl and Spanish. The Boban calendar wheel is the result of a succession dispute following the Inquisitions burning of don Carlos Ometochtli and in which don Antonio Pimentel Tlahuitoltzin, seated above right, asserts his legal right to be ruler of Texcoco de Mora, with the support of don Hernando de Chávez, the figure on the upper left.

The outside ring of the calendar as well as the central three part history is hand colored and probably drawn and composed by two hands. A reconstructed life size black and white photostat is included in the JCB bibliographical file.

John Carter Brown Library copy imperfect: top and bottom of calendar wheel heavily damaged with substantial loss of text. A lifesized electrostat copy of the calendar as reproduced in Colonel Doutrelaine's 1866 article is housed in the JCB bibliographical file along with xeroxes of the Appendix from Bonfires of Culture: Franciscans, indigenous leaders, and the Inquisition in early Mexico, 1524-1540 by Patricia Lopes Don, University of Oklahoma Press, 2010, "Un manuscrit méxicain de la collection Boban" by the Colonel Doutrelaine, printed in the Archives de la Commission scientifique du Méxique vol. VIII, Paris, 1866-1867, and "The Boban calendar wheel" by Charles E. Dibble, printed in Estudios de Cultura Náhuatl no. 20, 1990.

John Carter Brown Library copy encased in nonelectrostatic plexiglass housed in a large phase box so that it may lay flat.

Provenance of the John Carter Brown Library copy: Eugène Boban and C.F. Gunther: former owners from information present in the JCB bibliographical file.