Announcing the Digital Atlas of Medieval Dioceses and Provinces!

After five years of work, our wonderful team of student researchers has put the finishing touches on the Digital Atlas of Dioceses and Ecclesiastical Provinces in Latin Christendom (1200-1500)! All of the mapping files and their associated documentation can now be downloaded here, and are available for public use under a Creative Commons license.

The maps are necessarily limited by the constraints of source survival and the state of existing scholarship. It proved impossible to depict the ecclesiastical geography of the Latin East (with the exception of Cyprus), and the boundaries of many jurisdictions in eastern Europe are pretty vague (no doubt this was true in reality as well!). In other parts of Europe (notably Iberia and parts of central Italy), a certain amount of conjecture was necessary to deal with shifting boundaries and contested jurisdictional claims.

We welcome comments, corrections, and suggestions for future updates! 

CESTA Seminar Presentation

On October 15, 2019, members of the Corpus Synodalium project team presented the website and database at the weekly seminar series of Stanford’s Center for Spatial and Textual Analysis. Many thanks to the wonderful audience (both on-site and around the world, via Zoom video-conference) for such an enthusiastic response and so much helpful feedback!

Presenters: undergraduates Clara Romani (Stanford, ’20) & Thawsitt Naing (Stanford, ’19); and Prof. Rowan Dorin

Expanding the Digital Atlas – More Reflections from the Research Team

Work continues on the Digital Atlas of medieval ecclesiastical jurisdictions. Here Stanford undergraduate Lauren Schlansky (’19), who started working on the atlas in January 2019, reflects on her contribution:

« I joined the project about a year after its creation. Using existing maps and records, my predecessors on the project were able to create a digital map of diocesan boundaries in late medieval Europe. My primary role in the project has been to represent on a new layer of the map provincial jurisdictions in Medieval Europe between 1200 and 1500, and to accurately reflect the changes in jurisdiction between the different provinces. The provinces, which encompassed and presided over multiple dioceses, frequently gained and lost jurisdiction over different dioceses, making their representation on a single map challenging. The dynamic and interactive aspect of this map, however, affords us the ability to trace the changes in jurisdiction in Medieval Europe over time on a single map. Using the mapping software ArcGIS, I created multiple shapefiles for each province, in which each shapefile represents the province’s new boundary for a particular period of time. With a click of a button on the map, we can progress temporally — from 1200 to 1300, for example — and visually track the changes in provincial boundaries. Together, the digital map and the textual corpus of local ecclesiastical legislation, to which the map is connected, will allow us to better understand the movement and influence of laws, as new laws were promulgated or ignored by different regional, provincial, and diocesan jurisdictions over time. »

Creating the Digital Atlas – The Research Team Reflects

A key element of the CoSyn project has been the creation of a digital atlas of diocesan and provincial boundaries of medieval Latin Christendom. Stanford undergraduate Clara Romani (’20), who started working on the atlas in June 2017, shares her reflections: 

« Historical research is not always glamorous. In this case, however, it to some extent was. For this project, it involved cutting-age technology, mysteriously missing maps, and, occasionally, some creative (but well-grounded!) estimations.

My role in this project, along with that of [fellow Stanford undergraduate] Claire Womack (’20), fell on the cartographic side of things. It seemed simple enough: use existing maps to create a comprehensive, digital model of medieval ecclesiastical boundaries. We started by digitizing an excellent series of maps begun under Vatican auspices in 1930s Italy. We had to track down a few volumes mysteriously missing from the Stanford collections and resolve some conflicting boundary lines, but overall, we didn’t know how good we had it in those early days. Though much of Italy kept excellent records, other regions were not so accommodating. Medieval diocesan borders were ill-defined — or sometimes undefined — even by their contemporaries. In Spain, the ever-advancing Reconquista endlessly pushed and pulled at the boundaries of Christendom. In southern Italy, bishops quarreled over residual micro-dioceses, remnants of Byzantine colonization.

Over time, the project grew more and more complicated by poor records, missing sections, and chronological discrepancies between maps. However, with the help of ArcGIS mapping technology and the assistance of numerous colleagues at Stanford and other institutions, we were able to cobble together a rough snapshot of medieval Catholic geographical situation. Our work, brought to life by Thawsitt Naing, will now allow researchers to explore the visual, cartographic elements of this corpus of ecclesiastical legislation. »