A Wall of the Faithful: Spatial Analysis of Military Order Architecture on Medieval Iberia's Religious Frontier

In 1170, the military-religious Order of Santiago identified themselves as “a wall of the faithful” in their foundational Rule. As the premier Christian institutions residing on the fortified border between Christian and Muslim territory, Iberia’s military orders may have formed a metaphorical wall, but their architecture existed in a much more complex spatial system. These orders were so pervasive in Iberia that until now, scholars have considered a comprehensive survey of their architecture to be ‘impossible.’ This dissertation argues that regimented, data-driven methods make it possible to study patterns in the distribution and intention of military order architecture in Iberia in the mid 12th through 14th centuries. When combined with historical context, these patterns reveal strategies that have gone unnoticed in past scholarship.
Four patterns governing the manifestation of the wall of the faithful are represented at multiple spatial scales in this work. First, the Iberian military orders were founded at fortified sites that lie near the “edges” of Christian-controlled territory. Second, these sites were chosen based on their ability to surveil and influence the landscape. Third, the wall of the faithful was closer to a shifting, intervisible and/or spatially connected network than a linear wall. Finally, two architectural case studies reveal that the military orders were capable of and motivated to manifest their identity on the frontier through the construction of large-scale, fortress-monastery headquarters. By combining peninsula-wide patterns with in-depth studies of two sites – the fortress-monastery of Calatrava la Nueva and the Castillo-Convento de Montesa – this study reveals that the meager and isolated appearance of the hilltop fortresses of the military orders conceals the central role they played in the formation of a vast religious frontier.