¹ Research for this paper was supported by the Social Sciences and Humanities Research Council of Canada. I should like to thank Laura Marchiori and Stefano Riccioni for their assistance.

For the structure: Whitehead, P., ‘The church of SS. Cosma e Damiano in Rome’, American journal of Archeology 31 (1927), 11–18CrossRefGoogle Scholar ; Krautheimer, R., Corpus Basilicarum Christianarum Romae, 5 vols (Vatican City, 1937–1977), I, 137–43Google Scholar ; Episcopo, S., ‘SS Cosma e Damiano, Basilica’, in Steinby, E.M. (ed.), Lexicon Topographicum Urbis Romae, 6 vols (Rome, 1993–2000), I, 324–5Google Scholar ; Kalas, G., Sacred Image/Urban Space: Images, Installations, and Rituals in the Early Medieval Roman Forum (Ph.D. thesis, Bryn Mawr College, 1999), 108–72Google Scholar ; Tucci, P.L., ‘Nuove acquisizioni sulla basilica dei Santi Cosma e Damiano’, Studi Romani 49 (2001), 275–93Google Scholar ; and Brandenburg, H., Le prime chiese di Roma IV–VII secolo. L'inizio dell'architettura ecclesiastica occidentale (Milan, 2004), 222–31Google Scholar.

² As has been noted by many, including recently Brandenburg, Le prime chiese di Roma (above, n. 1), 222: ‘Si tratta del primo luogo di culto cristiano costruito nel vero e proprio centro monumentale di Roma’. For a discussion of the continuity in occupation and use of the Roman Forum during the late classical and earlv medieval periods, see Meneghini, R., ‘Il Foro Romano e i Fori Imperiali’, in Meneghini, R. and Santangeli Valenzani, R., Roma nel-l'altomedioevo: topografia e urbanistica della città dal V al X secolo (Rome, 2004), 157–88Google Scholar. The installation of a church also may have prompted the use of adjoining space for burial: Capponi, M. and Ghilardi, M., ‘Scoperta, nel ‘Templum Pacis’, di un'area sepolcrale probabilmente contemporanea alla fondazione dei SS. Cosma e Damiano’, in Guidobaldi, F. and Guiglia Guidobaldi, A. (eds), Ecclesiae Urbis. Atti del congresso internazionale di studi sulle chiese di Roma (IV–X secolo) (Vatican City, 2002), 733–56Google Scholar.

³ Duchesne, L. (ed.), Liber Pontificalis, 2 vols (Paris, 1886–1892), I, 279Google Scholar : ‘Hic fecit basilicam sanctorum Cosmae et Damiani in urbe Roma, in loco qui appellatur via Sacra, iuxta templum urbis Romae’. English translation from Davis, R. (trans.), The Book of Pontiffs (Liber Pontificalis) (Liverpool, 1989), 51CrossRefGoogle Scholar.

⁴ Krautheimer, R., Rome: Profile of a City; 312–1508 (Princeton, 1980). 32–58Google Scholar . For an overview of the ‘Christianization’ of the city, see also Pani Ermini, L., (ed.), Christiana Loca ‘Lo ‘spazio cristiano’ nella Roma del primo millennio’, in Pani Ermini, L. (ed.), Christiana Loca, Lo spazio cristiano nella Roma del primo millennio, 2 vols (Rome, 2000–2001), I, 15–37, esp. p. 29Google Scholar. Although archaeology in recent decades has led to some substantial rethinking of Krautheimcr's division of Rome into zones of abitato and disabitato, the general observation regarding the areas of focus for papal building projects still holds true.

⁵ Oakcshott, W., The Mosaics of Rome (London, 1967), 90–4Google Scholar ; and Kalas, Sacred Image/Urban Space (above, n. 1), 148–57. Pope Felix's activities at the site consisted primarily in the installation of these mosaics. The lower walls retained their fourth-century marble decorations in opus sectile. These were still in place in the sixteenth century when they were recorded by Pirro Ligorio and others: see Luschi, L., ‘Gli antichi edifici della basilica dei SS. Cosma e Damiano: osservazioni sui disegni ligoriani’, in Panoli Campanati, R. (ed.). Seminario intemazionale di studi sul tema ‘Ricerche in archeologia e topografia’ in memoria del Prof. Nereo Alfieri (XLIII corso di cultura sull'arte ravennate e bizantina) (Ravenna, 1998), 429–52Google Scholar. The apse mosaic was substantiallv restored in the late sixteenth century, and then again in the course of extensive renovations made to the church by members of the Barberini family in the seventeenth century: see Tiberia, V., Il restauro del mosaico della basilica dei Santi Cosma e Damiano a Roma (Todi, 1991)Google Scholar , and Tiberia, V., Il mosaico restaurato. L'arco della basilica dei Santi Cosma e Damiano (Rome, 1998)Google Scholar. Drawings made by Antonio Eclissi in the 1630s provide more details than are visible today: Osborne, J. and Claridge, A., The Paper Museum of Cassiano dal Pozzo. Series A, Part II: Early Christian and Medieval Antiquities, 2 vols (London, 1996–1998), I, 94–7Google Scholar.

⁶ Cosmas and Damian were physicians who practised their medicine without exacting payment. They thus belong to a category of Christian saints known as the anargyroi (literally those without silver, that is without money).

⁷ ‘… ut aetheria vivat in arce poli’. Full text cited in Duchesne (ed.), Liber Pontificalis (above, n. 3), I, 280, n. 3, and discussed below.

⁸ For this influence and a list of examples, see the comments of Nilgen, U., ‘Die Bilder über dem Altar. Triumph- und Apsisbogcnprogrammc in Rom und Mittelitalien und ihr Bezug zur Liturgie’, in Bock, N., de Blaauw, S., Frommel, C.I. and Kessler, H. (eds), Kunst und Liturgie im Mittelalter (Akten des Internationalen Kongresses der bibliotheca Hertziana und des Nederlands Instituut te Rom. Rom, 28–30 September 1997) (Beiheft zum Römischen Jahrbuch für Kunstgeschichte 33) (Munich, 2000), 75–89Google Scholar , at p. 76. The originality of the iconography has been the subject of considerable debate. Given the evident authority of this formula in subsequent centuries, some scholars have argued that the Santi Cosma e Damiano apse must have copied some unknown earlier model, now lost: see Hoogewerff, G.J., ‘Il mosaico absidale di San Giovanni in Laterano ed altri mosaici romani’. Rendiconti della Pontificia Accademia Romana di Archeologia 27 (1953), 297–326Google Scholar ; and Krautheimer, Rome: Profile of a City (above, n. 4), 93–4. An opposing argument, stressing the originality of the Santi Cosma e Damiano apse composition and claiming that it served as the direct model for later copies, has been presented by Nordhagcn, P.J., ‘Un problema di carattere iconografico e tecnico a S. Prassede’, in Roma e l'età carolingia (Rome, 1976), 159–66Google Scholar.

⁹ Sande, S., ‘Old and new in old and new Rome’, Acta ad Archaeologiam et Artium Historiam Pertinentia 17 (2005), 101–12, at p. 104Google Scholar.

¹⁰ Brandenburg, Le prime chiese di Roma (above, n. 1), 223.

¹¹ Brandenburg, Le prime chiese di Roma (above, n. 1), 223. For the parallel at Alexandria: Sinthern, P., ‘Der Römische Abbacyrus in Geschichte, Legende und Kunst’, Römische Quartalschrift 22 (1908), 197–239Google Scholar ; and Delehaye, H., ‘Les saints d'Aboukir’, Analecta Bollandiana 30 (1911), 448–50CrossRefGoogle Scholar.

¹² See Aronen, J., ‘La sopravvivenza dei culti pagani e la topografia cristiana dell'area di Giutuma e delle sue adiacenze’, in Steinby, E.M. (ed.), Lacus Iutumae I (Rome, 1989), 148–74Google Scholar ; Knipp, D., ‘The Chapel of Physicians at Santa Maria Antiqua’, Dumbarton Oaks Papers 56 (2002), 1–23CrossRefGoogle Scholar ; and Brenk, B., ‘Zur Einführung des Kultes der heiligen Kosmas und Damian in Rom’, Theologische Zeitschrift 62 (2006), 303–20Google Scholar. It is tempting to speculate that this proximity to a site of healing by water may have prompted the attention given in the apse mosaic to the river Jordan, singled out for identification by an inscription.

¹³ F. Coarelli, ‘Pax, Templum’, in Steinby (ed.), lexicon Topographicum Urbis Romae (above, n. 1 ), IV, 67–70.

¹⁴ Pliny, Natural History 34.19.84; see also 35.36.74, 35.36.101–2, 33.36.109 and 36.11.58. For the art collection: Lanciarli, R., New Tales of Old Rome (London, 1901), 233–4Google Scholar ; and La Rocca, E., ‘La nuova imagine dei fori imperiali: appunti in margine agli scavi’, Mitteilungen des Deutschen Archäologischen Instituts. Römische Abteilung 108 (2001), 171–213Google Scholar , esp. pp. 195–207. Prokopios of Caesarea (History of the Wars 8.21.11–14) recorded that part of the sculpture collection was still in place in the sixth century.

¹⁵ For the medieval and post-medieval phases of this structure, see Russo, A., ‘Il tempio di Romolo al Foro Romano: testimonianza stratigrafica di una fase medievale’, Archeologia Medievale 28 (2001), 241–66Google Scholar.

¹⁶ Kor the marble plan, see Claridge, A., Rome: an Oxford Archaeological Cuide (Oxford, 1998), 1 53–5Google Scholar ; and Kalas, Sacred Image/Urban Space (above, n. 1), 128–34. For the sixteenth-century rediscovery, see Jacks, P., The Antiquarian and the Myth of Antiquity: the Origins of Rome in Renaissance Thought (Cambridge, 1993), 218–20Google Scholar.

¹⁷ Kalas, Sacred Image/Urban Space (above, n. 1 ), 157.

¹⁸ Yarden, L., The Spoils of Jerusalem on the Arch of Titus: a Re-investigation (Stockholm, 1991)Google Scholar.

¹⁹ Josephus, , The Jewish War Books 5–7, trans. Thackeray, H. (Cambridge (MA), 1961[1928]), VII, 158–62Google Scholar.

²⁰ See Nov, D., ‘Rabbi Aqiba comes to Rome: a Jewish pilgrimage in reverse?’, in Eisner, J. and Rutherford, I. (eds), Pilgrimage in Craeco-Roman and Early Christian Antiquity: Seeing the Gods (Oxford, 2005), 373–85Google Scholar.

²¹ The claim is made in the Descriptio Lateranensis Ecclesiae, the first edition of which may be dated to the late eleventh century: see R. Valentini and Zucchetti, G. (eds), Codice topografico della città di Roma, 4 vols (Rome, 1940-53), III, 337Google Scholar . See also Herklotz, I., Gli eredi di Costantino. Il papato, il Luterano e la propaganda visiva nel XII secolo (Rome, 2000), 172–3Google Scholar.

²² Prokopios, History of the Wars 4.9.1 - 10. Whether the objects stolen by the Vandals and recovered by Bclisarins were the originals, or later replacements masquerading as such, is immaterial. What is important is that thev were believed to be the originals in the early sixth century.

²³ For example, the Descriptio Lateranensis Ecclesiae (Valentini and Zucchetti (eds). Codice topografico della città di Roma (above, n. 21 ), III, 336–9, 341–2) and the Graphia Aureae Urbis (Codice topografico della città di Roma, III, 83–4). Both refer explicitly to the inclusion of ‘septem candelabra’. The Graphia confusinglv located the Templum Pacis ‘iuxta Lateranum’, no doubt influenced by the latter's claim to possess the objects in question. The memory of the transfer from Jerusalem was also preserved by Jerome, Commentaria in Joelem Prophetam Migne, J.P., Patrologiae Cursus Completus Series Latina (Paris, 1844-91), XXV, 1, 029)Google Scholar.

²⁴ Matthiae, G., SS. Cosma e Damiano e S. Teodoro (Rome, 1948), 49–65Google Scholar , contended that the arch mosaics were not contemporary with the apse, belonging instead to the pontificate of Sergius I (687–701) in the late seventh century. This view was prompted in large part by Pope Sergius's known efforts to promote the theme of the agnus Dei, the celebration of which he introduced to the canon of the Mass: see Duchesne (ed.), Liber Pontificalis (above, n. 3), I, 376. However, the prevailing view maintains that the decorations of apse and arch form part of a unicum. Kor a recent discussion, see J.L. Opie, ‘Agnus Dei’, in Guidobaldi and Guiglia Guidobaldi (eds), Ecclesiae Urbis (above, n. 2), 1,813–40, esp. pp. 1,829–30, and the subsequent comments by P.J. Xordhagcn (p. 1,844). This view is largely confirmed by the technical analysis of the mosaic tesserae: see Tiberia, Il mosaico restaurato (above, n. 5), 81–7, in which most of the colours of the tesserae used in the apse and on the arch have been found to be chemically similar. Most curiously, despite the lack of corroborating evidence, and a clear ‘assenza di riscontri obiettivi’ (p. 1 5), Tiberia none the less accepted Matthiae's judgement of the dating on stylistic grounds. The later dating for the arch mosaics has been supported also by Wisskirchen, R., ‘Zur Apsissternwand von SS. Cosma e Damiano/Rom’, Jahrbuch für Antike und Christentum 42 (1999), 169–83Google Scholar.

²⁵ van der Meer, F., Maiestas Domini: Théophanies de l'Apocalypse dans l'art chrétien (Rome, 1938)Google Scholar . A useful overview of the influence on church decoration has been provided by Kinncy, D., ‘The Apocalypse in early Christian monumental decoration’, in Emmerson, R.K. and McGinn, B. (eds), The Apocalypse in the Middle Ages (Ithaca (NY)/London, 1992), 200–16Google Scholar.

²⁶ The original San Paolo arch mosaics were lost in the disastrous fire of 1823, but are recorded in antiquarian drawings, and in particular Biblioteca Apostolica Vaticana, MS Barb. Lat. 4406, fols 137v–138r: see Waetzoldt, S., ‘Zur Ikonographie des Triumphbogenmosaiks von St Paul in Rom’, in Miscellaiiea Bihliothecae Hertzianae (Munich, 1961), 19–28Google Scholar ; and Bordi, G., ‘Il mosaico dell'Arco Triomphale’, in Andaloro, M. (ed.), L'orizzonte tardoantico e le nuove immagini, 312–468 (La pittura medievale a Roma 312–1431. Corpus I) (Milan, 2006), 395–407Google Scholar . The inscription, naming the Empress Galla Piacidia and Pope Leo I, permits a dating between 440 and 450. For additional comments on the tao arches, and the possible influence of contemporary commentaries on the Apocalypse, see Davis-Weyer, C., ‘Discedente Loth a Sodomis: a Ticonian reading of the mosaic on the arch of SS. Cosma e Damiano in Rome (526–530)’, in Arte d'Occidente: temi e metodi. Studi in onore di Angiola Maria Romanini (Rome, 1995), 743–53Google Scholar . Millennialist concerns seem to have prompted renewed interest in Apocalvpse imagen in the fifth century, and while no illustrated manuscript copies of the text sun ive from this era, it is widelv believed that the ninth-centurv Trier Apocalypse (Stadtbibliothek, cod. 31 ) copies an earlier Italian model.

²⁷ As rccentlv noted by Herbert Kessler in his discussion of the murals on the triumphal arch at Ferentillo: see Kessler, H., ‘Il ciclo di San Pietro in Valle: fonti e significativo’, in Tamanti, G. (ed.), Gli affreschi di San Pietro in Valle a Ferentillo: le storie dell'antico e del nuovo testamento (Naples, 2003), 77-116, at p. 81Google Scholar.

²⁸ Mommsen, T. (ed.), Chronica Minora (Monumenta Germcmiae Historica, Auetores Antiquissimi IX) (Berlin, 1892), 195Google Scholar . See also P. Frederiksen, ‘Tvconiiis and Augustine on the Apocalvpse’, in Fmmerson and McGinn (eds), The Apocalypse in the Middle Ages (above, n. 25), 20–37, esp. pp. 35–6.

²⁹ For example Bede, On the Temple, trans. S. Connolly (Liverpool, 1995), 5: ‘The house of God which King Solomon built in Jerusalem was made as a figure of the holy universal Church’.

³⁰ In this context it is also interesting to consider that by the fifth centim Rome was thought of as the spiritual successor to Jerusalem: see, most recently, Kessler, H., ‘Rome's place between Judaea and Francia in Carolingian art’, in Roma fra Oriente e Occidente (Settimane di studio del Centro italiano di Studi sull'Alto Medioevo XLIX) (Spoleto, 2002), 695–718Google Scholar ; and Warland, R., ‘The concept of Rome in late antiquity reflected in the mosaics of the triumphal arch of S. Maria Maggiore in Rome’, Acia ad Archaeologiam et Artium Historiam Pertmentia 17(2003), 127–41Google Scholar.