The Historia general de las cosas de Nueva Espa�a (“General History of the Things of New Spain”) is a sixteenth-century manuscript created by an unknown number of Nahua tlacuiloque in collaboration with a Spanish friar, Fray Bernardino de Sahag�n, for the purpose of documenting Aztec culture and acquiring Nahuatl literacy to facilitate Catholic assimilation. Within the three volumes and twelve libros produced over the course of thirty years, Book X, “The People,” describes the social and corporal composition of the Nahua world, with detailed lists of social identities, body parts, and Indigenous ethnic groups residing in central Mexico. Several scholars have examined this text for evidence of a Nahua-Christian moral dialogue, but few have addressed three additional features of Book X: the overall correspondence and difference between the original Nahuatl text on social identities and its Spanish translation; the brevity of information included in the descriptions of documented social types; and the possibility of missing critical details resulting from the concise texts. This thesis re-evaluates our current understanding of Book X relative to these three understudied topics. In my close analysis of “The People,” I first apply the "three texts-in-one" approach to examine degrees of rhetorical correlation between the Nahuatl-language passages, corresponding Spanish translations, and accompanying illustrations in constructing discourses of morality in the tenth libro. Next, I cross-examine Book X with other Books of the Florentine Codex to determine critical details that were omitted from the descriptions of social types. Third, I locate identities and information mentioned in other areas of the Historia general, but omitted from the writings. This project contributes to literature regarding Book X by identifying additional moral rhetoric present in the three texts, and by challenging the current perception of the “catalog” as a comprehensive list of social identities.