The first phase of the methodology is obtaining computer–readable files from the more comprehensive editions of the RGs. We began with Francisco del Paso y Troncoso’s Papeles de Nueva España, which contains a significant portion of the corpus. Transcriptions from the original manuscripts were already available in electronic format, but it was necessary to identify and correct significant errors caused by the Optical Character Recognition (OCR) software. This is a common problem with old documents, to which Alpert–Abrams offers an approach in her 2016 article on the corpus known as Primeros Libros.

After completing six volumes of Papeles de Nueva España (Del Paso y Troncoso 1905), the work continued with the RGs from Yucatán, published in volume 11 of Colección de documentos inéditos de las posesiones de España en ultramar (1898). Additionally, thanks to a generous permission from the National Autonomous University of Mexico (UNAM), we were also able to digitize a more recent version of the 54 RGs from Yucatán transcribed and edited by De la Garza (1983) and to acquire in a digital format 114 RGs published in ten volumes by Acuña (1982–1988). In the end, we obtained two versions of the whole corpus in machine–readable format: the first one includes the notes, references and commentary from the scholars who transcribed and studied the documents, while the second contains only the transcription of the original RGs texts. A third version that includes all the NLP annotations was produced during the third phase of the project.

The second phase starts with a compilation of all the place names that exist in the corpus as well as many others from relevant sources, and then solving any linguistic and locational uncertainties that prevent their unequivocal identification.

The third stage comprises four tasks: defining an annotation schema by selecting the most relevant analytic categories for the intended historical analysis; annotating manually, and in accordance with the previously defined annotation schema, two different samples of documents: one for training the NLP deep-learning model and another one to validate it; tuning the deep-learning model to automatically perform name entity recognition, disambiguation and classification, in order to obtain a fully annotated corpus; and assessing the performance of the model in accordance with the gold-standard validated by experts.

One area of application for the techniques detailed in this study is understanding the coexistence of competing systems of land ownership and labor in New Spain during the colonial period. In New Spain during the short time of compilation of the RGs, there was a strong debate about the system of encomiendas and the desire to replace it with the so-called repartimientos. The encomienda was the right to exploit the labor of indigenous populations, granted by the Spanish Crown to conquistadors, who at the beginning of the colonization held this privilege in perpetuity and could, therefore, pass it to their descendants with little intervention from the royal government in Madrid. In contrast, the repartimiento only allocated the labor force of native workers for a fixed period of time in exchange for a meager remuneration. The latter gave the royal government more control over its subjects and resources. Neither the holders of encomiendas nor repartimientos were allowed to appropriate lands, as private property was reserved for haciendas. These three systems coexisted in the 1570s despite the enactment of the so-called New Laws in 1542, which attempted to protect the rights of the indigenous populations and prevent the dispossession of their lands by abolishing the encomiendas. Throughout the texts of the RGs, therefore, it is common to find claims by conquistadors’ descendants of their encomienda rights, and others defending the benefits of repartimientos. A comprehensive study of the claims and contentions found in the RG corpus would improve our understanding of the period.

A second application of these methodologies has to do with disambiguating local structures of governance in New Spain. The early colonial period was a time when the functions and spheres of influence of the four branches of colonial government were not well defined, and consequently the spatial boundaries of the judicial, administrative, military and ecclesiastical jurisdictions overlapped (Figure 10). This was especially true at the municipal level. Consequently, the corpus contains terms associated with several kinds of jurisdictions whose meanings were not consistent throughout the vast territory of New Spain (e.g. partidos de clérigos, distrito de mision, custodia, guardianía, vicaría, presidencia, etc.). The subject has been a matter of ongoing debate among historians [Gerhard 1972b, 66], but we believe that applying collocation analysis for extracting the contextual use of such words would shed light on how those institutions functioned in parallel to alcaldías mayores and corregimientos and this would be an important contribution to the knowledge of this period.

A third area for future study has to do with demarcating the boundaries of territories in New Spain. By reading the RGs, we could attempt to identify the names and boundaries (linderos) of towns belonging to corregimientos (territorial demarcations for administrative and judicial purposes) mentioned in the corpus. Circa 1570, there were 200 of such units whose frontiers have been outlined by Gerhard (1972a). However, the smaller demarcations (towns, villages) suffered adjustments in boundaries and jurisdictions. As Gerhard points out, at the time of the RGs, “[e]arly civil and ecclesiastical divisions lost importance and were eliminated; others came into being as a result of conquest, proselytization, mining activity, and other causes” [Gerhard 1972b, 66–9]. The application of a mathematical model that analyzes the maximum available territory around each settlement within a region, like the one proposed by Ducke and Kroefges (2008), could provide preliminary hypotheses on such demarcations. These would then be tested against the actual historical information extracted from the corpus through geographic collocation analysis. One of the many ways that such a study could begin is by extracting references on the routes that local administrators take for their visits to towns within their jurisdiction, the distances they traversed, the geographic features and topography of the landscape, etc. (Figure 10) This, and much other information, is available throughout the corpus, but more specifically in the answers to questions 7, 8, 11, and 12 (see Appendix 1).

A fourth research question has to do with our understanding of the outbreak of disease (1576-1581) that took the lives of half the population of New Spain during the early colonial period [Acuña–Soto et al. 2004]. This was the second time that cocoliztli (as the epidemic was called) had decimated the native population, causing the disappearance of whole communities, shortages in labor-force for the encomiendas and repartimientos, the displacement of people over different regions, or, on the contrary, the congregation of survivors (sometimes of different ethnic communities) in new Indian towns, all of which altered dramatically the traditional settlement pattern [Gerhard 1972a, 24]. How did this phenomenon vary over different regions? How many people died in each locality? How did this epidemic compare with others in the past? How did the new settlement change in comparison with Prehispanic times? These are all questions that GTA could help to answer by collocating words and phrases related to health (such as diseases, symptoms, and remedies) and analyzing them with spatial mathematical models of disease contagion.

A fifth application of our methodology has to do with the study of natural resources. GTA will allow the extraction and analysis of regional historical information on natural resources such as plants. There are already interesting archaeological, historical and ethnographic research related to plants and their use in Mesoamerica, medicinal and otherwise [Albores Zarate 2015] [Chávez Mejía et al. 2020] [Hersch 1999]. Some further research has been also dedicated to assessing the importance of the trees and edible plants introduced by Europeans. With the annotation of the RGs in this project and the development of GTA, it is now possible not only to extract information regarding native and European plants introduced in the different regions of New Spain, but also to contribute to further debates. It is known, for instance, that Mesoamerican cultures had an extended knowledge of plants for medicinal use and most of the research about this has been carried out using colonial primary sources. We could now create a map of all the plants mentioned in the RGs and compare this dataset with archaeological data and other primary sources that were dedicated to the recording of medicinal plants, such as the Códice Badiano or the Historia Natural de Nueva España. This would allow researchers, for instance, to assess the continuation in the use of specific plants for remedies and consumption in specific regions of New Spain. Other interesting avenues of possible research with GTA analysis are the availability of food and animals both native and introduced, the use of natural resources, the existence of cultural artefacts, the presence of priests and religious orders in particular regions, as well as types of architecture.

An additional topic is the study of exchange networks and trading practices, as well as communication routes, both terrestrial and aquatic, among the populations described in the RGs. One such study has already been conducted by Favila-Vázquez (2019), who successfully reconstructed aquatic communication networks in the Rio Balsas region by extracting information from the responses available to queries 38 to 47 of the RGs (Figure 11). These contain crucial data regarding navigation by sea, including location of ports and coastal landscape. Together with data from question 19 (focused on fluvial networks), the extraction of data from the RGs corpus allowed Favila-Vázquez to reconstruct a riverine and coastal system of communication that explains the spatial connectivity of the Valley of Mexico to the Pacific coast.