THE ROTUNDA AND THE SIDE HALLS

This second volume deals with the history of the Templum Pacis from late antiquity onward and, in particular, with the metamorphosis of the great hall (the Library of Peace) that, after two millennia, is still a living space – the basilica of SS. Cosma e Damiano. Most of the visitors to the basilica ignore that inside that space, centuries earlier, they would have met with Aulus Gellius and Galen, Domitian and Septimius Severus, Felix IV and Urban VIII, and with many Renaissance artists and antiquarians, such as Piero della Francesca and Pirro Ligorio. As I explained in the preface, this two-volume book is a monograph on the Templum Pacis, from antiquity to present, and I wish to collect and present whatever evidence is available in order to define as precisely as possible what that evidence implies in the study of Vespasian's building. The next chapters, even those that might seem to be unrelated to the Templum Pacis, in fact contribute to our understanding of that architectural complex; my analysis of the late antique, medieval, and Baroque remodelings of the great hall, along with the Renaissance and nineteenth-century excavations of the Templum Pacis, is not mere documentary information; rather, it solves many research problems and, at the same time, shows how religious, economic, social, and political factors affected the architectural complex.

For example, in the first half of the fourth century AD, the library hall was dismantled and transformed into an audience hall of the praefectus Urbi. Thanks to my survey and a series of medieval and Renaissance documents, I can argue that the rotunda, the first step in an extremely long remodeling, does not date from the time of Maxentius, and I can demonstrate that the entire renovation is Constantinian in date. Note that, unlike the imperial forums and the buildings located in and around the Roman Forum, only the Flavian monument was radically remodeled in late antiquity; in particular, the rotunda was covered by one of the latest concrete domes built within the city walls, whereas the new apse of the great hall preserves the oldest surviving semidome built with terracotta tubes.