In the late Postclassic period (ca. 1250–1521), which immediately precedes the Spanish conquest, the practice of recording a number of subjects—including history, timekeeping, religion, tribute, botany, and genealogy—in manuscripts was widespread in Mesoamerica (comprising parts of modern-day Mexico and Central America). The significance of Mesoamerican manuscripts cannot be overstated; however, analyzing them is an arduous exercise. Unlike the Maya, who developed hieroglyphic writing, the Aztecs (also Nahuas) used imagery and calendar glyphs exclusively. After 1521, during the colonial period, the manuscript-making practice continued and indigenous scribes adopted alphabetic text, which elucidates images and glyphs in Pre-Columbian manuscripts. Yet, the complexity of sixteenth-century society, straddling an esteemed indigenous past as it confronted new cultural realities, particularly the advent of Christianity and Aztec responses to the new religion, renders colonial manuscripts difficult to study. While Mesoamerican manuscripts have been widely analyzed, some, including the Aztec Codex Mexicanus (ca. 1580s)—currently conserved at the Bibliothèque nationale de France—have not been the object of comprehensive examinations. This particular manuscript remains essential to Mesoamerican studies as scholars reference it in discussions of the conquest, calendar, droughts, and other topics. Surprisingly, only Ernst Mengin's 1952 commentary has analyzed the manuscript in its entirety.

Consequently, the current volume by Lori Boornazian Diel, an accomplished art historian who has contributed an impressive list of highly relevant and influential publications on Mesoamerica, is a welcome endeavor. Before Diel's work, scholars generally regarded the Codex Mexicanus—consisting of fifty-two plates featuring imagery, calendar glyphs, and glosses in Nahuatl, the Aztec lingua franca—as an amalgam of themes including calendars, medical astrology, history, and Nahua genealogy. With historic and iconographic evidence, Diel demonstrates that far from presenting disjointed almanacs, the manuscript offers a cohesive compendium that the Nahuas devised to function in colonial society. Diel builds on previous studies arguing that the Codex Mexicanus was modeled after Repertorios de los tiempos, Spanish books featuring a myriad of themes to help guide early modern Spaniards in their daily life. Similarly, Diel contends, the Codex Mexicanus guided Nahuas' quotidian endeavors in colonial New Spain, as evidenced by the manuscript's embrace of European culture, particularly Christianity, alongside indigenous precedents including artistic conventions.

This book presents a range of substantive material in six chapters and two appendixes with transcriptions, translations, and commentary of Nahuatl script that all readers—from the general public to beginner students, emerging scholars, and experts in the field—will appreciate. Chapter 1 opens with a concise thesis and summary of the book's contents and an overview of the Mesoamerican manuscript-making tradition. In chapter 2, Diel examines the Mesoamerican and European calendars, discusses how they are suffused with religious beliefs, and explains why the Codex Mexicanus incorporates a “hybrid” calendar that is simultaneously Mesoamerican and Christian. Diel interprets Nahua adherence in the Codex Mexicanus to both calendrical traditions—Mesoamerican and Christian—to correlate them (and the celebrations they mark in each religion) as a synthesis that effectively constructed “a new conception of time” and befitted colonial realities (19). Chapter 2's central argument is that indigenous conventions were not destroyed and lived on incorporated into the new society in Christian New Spain. Nevertheless, there were some missed opportunities to explore aspects of the calendar that would have strengthened this chapter. For example, Diel notes that Gordon Brotherston has argued that the Nahuas included the native calendar in the Codex Mexicanus to demonstrate that the Mesoamerican calendar was superior to its Christian counterpart (19). Brotherston's suggestion is particularly provocative when considering that the Julian calendar that Christian Europe used at the time was, by the sixteenth century, approximately two weeks out of sync with the movement of the sun due to its failure to account for leap years accurately. Consequently, Europeans devised the Gregorian as a replacement in 1582, which, incidentally, is around the time scholars estimate the Codex Mexicanus was painted. Diel does not really address this issue or explain why the Nahuas would enthusiastically embrace a calendar that was not only less familiar to them but also less accurate. Additionally, Diel briefly touches on Susan Spitler's argument that indigenous scribes' inclusion of the Christian calendar in the Codex Mexicanus was an intellectual endeavor, a type of “reverse ethnology,” similar to Europeans' striving to learn about the Nahuas (36). Delving into the cross-cultural intellectual exchanges that Spitler discusses in greater depth, including the scope of possibilities that could have emerged from this exchange, both as they relate specifically to the calendars and, more broadly, would have been a welcome addition to this book.

Chapter 3 provides further support that the seemingly disparate components of the Codex Mexicanus actually cohere. It discusses how the manuscript merges European medical astrology with Mesoamerican notions of how astronomy influenced the human body and argues that Aztec scribes included this information because of the epidemics afflicting indigenous peoples at this time, which confounded Nahua doctors. Chapter 4 builds on the work of Delia Cosentino, Justyna Olko, and others to analyze how the Aztecs recorded genealogy in the Codex Mexicanus. It clarifies data on Plate 9, which Diel reports features “one of the few pictorial genealogies” known on the Aztecs and “is by far the most extensive” (74). Diel explains certain tactics the Aztecs used including emphasizing the rulers' divine lineage. While Diel recognizes that scholars disagree about what specific glyphs and images refer (she provides her own interpretations, summarized in Table 4.1), her larger point is how Nahuas recorded their history in this particular manuscript to fit current sociopolitical realities. This chapter alone is an enormous contribution that will elicit and facilitate subsequent studies. A thought-provoking contention Diel offers is that “many of these native genealogies were created in the Tlaxcala-Puebla region” and presented alongside maps because “their ultimate function was to secure a particular family's ties to land,” a commodity directly linked to power via filial ties in central Mexico (92). Diel asserts that for the Nahuas, legitimizing their illustrious past was a “foundation for the Christian present” (93). Chapter 5 analyzes the Aztec annals in the Codex Mexicanus (Plates 10–52), including migration stories (a recurrent Mesoamerican theme), Aztec imperial history, and Tenochtitlán in the colonial period when it became New Spain's capital. Diel's evaluation of the evidence leads her to conclude that with the Hispanization of New Spain, the Aztecs “became key figures in Christian history and earned a path to salvation” (160). Finally, chapter 6 provides a summary of the book's arguments and an epilogue in which Diel traces the journey of the Codex Mexicanus from its native Central Mexico to Paris by reconstructing a probable archival history, some of which comes from “strange inscriptions” in the manuscript (Plate 19) that she dates to the eighteenth century.

Overall, Diel's book is a useful and notable contribution to Mesoamerican scholarship in general and Pre-Columbian and colonial manuscript study specifically. Scholars of religion will find this book particularly valuable, as the Nahua scribes who created the Codex Mexicanus were, according to Diel, simultaneously striving to be recognized as Christians even while recording and preserving their indigenous past. Significantly, Diel acknowledges that some of the book's arguments are her own interpretations and recognizes the possibility of alternate conclusions, thus providing a starting point for further discussion and scholarship. The book's strengths include Diel's analysis of each plate in the Codex Mexicanus, the high-quality reproduction of the entire manuscript in full color, and tables to help readers along. Even those who may disagree with some of Diel's conclusions or wish to suggest other interpretations will find this book to be an invaluable reference for their own work. Diel's arguments and suggestions elicit novel ways of evaluating the Codex Mexicanus, Mesoamerican manuscript-making tradition, and Amerindians' experiences in colonial society including their struggle in the sixteenth century to reconcile the preservation of their traditions with their embrace of Christianity.