This elegantly presented work consists of three parts. As a stand-alone work, there is a study of the codex in two parts, one written by each of the authors. In addition, there is a slipcase that contains facsimiles of the codex itself and related documents including the related Humboldt Fragment 1, the Veinte Mazorcas Codex, the Lienzo de Tlapa, the Lienzo de Chiepetlan, and the Lienzo de Azatepec. The area from which these documents proceed is in the modern state of Guerrero, deep in the mountains bordering the state of Oaxaca. This work is a welcome addition to the growing list of in-depth studies of native pictorial manuscripts.

As one can infer from the name, the codices are native pictorial documents from this region. Codices 1 and 2 were acquired by the Mexican National Institute of Anthropology and History (INAH) in the early 1940s; the larger of the two fragments carries the name Azoyú 1; the smaller is Azoyú 2. The Lienzo de Tlapa was acquired at the same time. The Humboldt Fragment 1 is one of 16 pictorial manuscripts acquired by Alexander von Humboldt during his travels in Mesoamerica, and is intimately related to the Azoyú codices and to the Lienzo de Tlapa. Together, these documents, which date from the colonial period but document events and activities across hundreds of years before and after the conquest, provide an intimate glimpse into the tlapaneca state of Tlapa-Tlachinollan. Vega Sosa and Oudijk have given valuable insights into the interpretation of these manuscripts and placed them within a larger historical context. The Tlapanecos occupied the mountainous region of Guerrero, north and east of Acapulco. Their language is part of the Otomanguean language family, not directly related to Nahuatl.

Vega Sosa and Oudijk each wrote an essay to accompany the document facsimiles. Vega Sosa focuses on the relationship of the Azoyú 2 codex with the Humboldt Fragment 1, specifically in terms of the tribute records that each contains for the Tlapa-Tlachinollan Kingdom These records span nearly 150 years, from 1425 to 1564. In her study, Vega Sosa recreates the reigns of each of the lords of Tlapa-Tlachinollan, and identifies the glyphs for each of the subject villages. She also looks at the calendar round as it was celebrated in the region and traces the history of the region including the Spanish conquest and evangelization by the Augustinians, as reflected in the tribute record. In general she finds that information in the Azoyú Codex 2 complements that of the Azoyú 1. They are frequently called twin documents since they overlap in so many ways. Neither document covers the years immediately preceding the Spanish conquest, except for fragmentary information. Curiously, Vega Sosa does not refer to work done by Gerardo Gutiérrez and others in their book on the Azoyú 2 and the Humboldt Fragment.

For his part, Michel R. Oudijk looks at the pictographic elements in all of the documents to derive an understanding of the nature of polity and state in the mountainous region of Guerrero. After presenting each of the documents included as facsimiles, Oudijk walks the reader through the method used to read the pictorial elements and decipher their content. He has an excellent section that deals with the nature of the complex polity known as the Kingdom of Tlapa-Tlachinollan. After a discussion of the historical elements in the documentation, Oudijk posits that the Azoyú codices were made to resolve issues of succession. He attributes the small discrepancies he finds between the two main codices to differing views of the issue of succession. He notes also that drawings in Azoyú 1 were rendered in a style more similar to that of the Nahua in central Mexico, while Azoyú 2 might reflect a local Tlapaneca tradition. Moreover, the two moieties within the kingdom, Tlapa and Tlachinollan, had probably been independent of one another prior to 1421 when a single ruler combined them.

This work is lovely, with very high production values. For scholars interested in Mesoamerican pictorial manuscripts, it is essential, especially because it brings together so many different works that deal with a single native political construct: the Kingdom of Tlapa-Tlachinollan.