These maps depict the boundaries of Catholic dioceses and ecclesiastical provinces in late medieval Europe, ca. 1200-ca. 1500. They include boundary information for more than eight hundred jurisdictions, covering nearly all of Latin Christendom with the exception of parts of eastern Europe and the Latin East (for which too little evidence survives). Given the shifting, contested, and often indeterminate boundaries of dioceses and provinces during this period, the maps are intended to be illustrative rather than definitive. Corrections and refinements are welcome.