The life of the Basilica of San Paolo fuori le Mura in Rome: Architectural renovations from the ninth to the nineteenth centuries

The Old Basilica of San Paolo fuori le mura in Rome was built at the end of the fourth century to enshrine, protect, and exalt the relics of St. Paul. As a bastion of Rome's apostolic legacy, an embodiment of papal authority, and an important monastic presence, Old San Paolo was one of Christianity's most venerable churches and---along with Old St. Peter's---the principal pilgrimage destination in Rome. In this dissertation, I trace a substantial and understudied portion of the life of the Old Basilica of San Paolo by examining architectural renovations in and around the basilica between the ninth and nineteenth centuries.; The dissertation's principal chapters present case studies of significant renovations. My first chapter examines the impact of Iohannipolis , an enclave built in the ninth century to protect the basilica, its adjacent monastery, and more generally the city of Rome. In the second chapter, I study the massive dividing wall built during the twelfth century across the transept in such a way that effectively split the core of the basilica and significantly altered its interior. In the third chapter, I concentrate on three distinct eighteenth-century renovations (the narthex, the Chapel of the Crucifix, and the baptistery) that gave the basilica its final guise. Because the Old Basilica and most of its renovations were destroyed by fire in 1823, my sources are restricted to written evidence and images. Although the collection and cataloging of these sources is an important contribution of the dissertation, more significantly, the overture to under-studied historical periods and neglected topics of investigation as well as a rigorous approach toward the extant sources allow me to delineate a richer and more complete history of the basilica.; In broad terms, the emphasis on renovations offers a valuable approach to the longue duree that is applicable to any object---a building, an icon, or a reliquary---that is layered in renovations. In the specific case of San Paolo, the new-found breadth of historical knowledge situates the basilica in its rightful, central place in the history of Roman ecclesiastical architecture.