ARCON – After Rome, Before Constantinople: Revealing the Late Roman Capital City of Nicomedia
Funded by the British Academy, ARCON – After Rome, Before Constantinople: Revealing the Late Roman Capital City of Nicomedia investigates how fragmented, dispersed and endangered archaeological heritage in modern urban contexts can be documented, contextualised and reinterpreted. By integrating diverse strands of evidence, including archaeology, digital mapping, heritage science and museum-based research, the project seeks to reconstruct ancient urban landscapes shaped by destruction, concealment and long-term environmental change.
At the heart of this research is ancient Nicomedia, modern İzmit in Türkiye, a key centre of the Tetrarchic world and the Roman imperial capital before Constantinople. Its significance is closely tied to Emperor Diocletian’s reign, which marked a turning point in Roman history through the establishment of new imperial capitals outside Rome. As Diocletian’s eastern capital, Nicomedia played an important role in the political, artistic and architectural transformations of Late Antiquity. Yet, while Rome and
Constantinople have long dominated scholarship, the role of centres such as Nicomedia remains less fully understood.
Largely hidden beneath modern İzmit, Nicomedia’s archaeological record presents an important case study for post-disaster urban archaeology. Repeatedly shaped and ultimately obscured by seismic destruction, the city has also been rediscovered through the aftermath of a modern earthquake. Following the 1999 İzmit earthquake, significant remains were revealed beneath damaged modern structures, including painted statues, marble reliefs and architectural fragments, later identified as remnants of Diocletian’s lavishly decorated palace complex. Today, these vulnerable discoveries are threatened by rapid modern development and seismic risk. Building on earlier TÜBİTAK-supported research, ARCON responds to this need by creating a digital archaeological map of the city for the first time. Through GIS-based digital mapping and archaeometric analysis, the project investigates legacy and archival data, archaeological remains, building materials, pigments and urban context to better
understand the relationship between architecture, material culture, environmental change, post-disaster landscapes and heritage risk.
The significance of this methodology extends beyond Nicomedia itself. ARCON uses these findings to reassess the wider artistic and ceremonial landscape of the Tetrarchic world, comparing Nicomedia with other imperial centres such as Milan, Sirmium, Trier, Thessaloniki, and Split.
The project further applies its research framework to related endangered materials revealed by post-disaster archaeology across Anatolia, including the Dardanos
Tumulus near Troy. While Nicomedia highlights the impact of earthquakes on ancient cities, Dardanos foregrounds the importance of reconnecting dispersed archaeological evidence with its wider spatial, material and environmental contexts, particularly in relation to fire-affected landscapes and the risks posed by wildfire and other forms of environmental change.
By developing new approaches to at-risk and post-disaster archaeology, ARCON seeks to protect endangered heritage while reassessing Western Anatolia’s contribution to the Late Roman world and the wider ancient Mediterranean. The project aims to validate these vulnerable discoveries before they are further obscured or lost, thereby strengthening cultural heritage awareness and encouraging more context-sensitive approaches to modern urbanisation.
ARCON – After Rome, Before Constantinople: Revealing the Late Roman Capital City of Nicomedia is hosted by the Faculty of Classics at the University of Oxford and led by Professor Tuna Şare Ağtürk.
The project is funded through the British Academy Global Professorships 2024 Programme and began in August 2025.
The British Academy
The British Academy is the UK’s national academy for the humanities and social sciences. Its Global Professorships programme supports outstanding international researchers to undertake ambitious, long-term research projects in the UK.
Further information about the Global Professorships programme is available here:https://www.thebritishacademy.ac.uk/programmes/global-professorships/
Through this support, ARCON brings together research on the Late Roman world and the wider ancient Mediterranean, art and architecture, urban archaeology, digital documentation, heritage science and public engagement to develop new approaches to endangered archaeological heritage, post-disaster urban archaeology and context-sensitive heritage preservation.
Project partners, collaborating institutions and local stakeholders
Project partners, collaborating institutions and local stakeholders include the Turkish Ministry of Culture and Tourism / General Directorate of Cultural Heritage and Museums; TÜBİTAK, the Scientific and Technological Research Council of Türkiye; Harvard Radcliffe Institute of Advanced Study; Çanakkale Onsekiz Mart University; Kocaeli Archaeology Museum; Troy Museum; İzmit Municipality; and other project partners and collaborators.
Principal Investigator:
Professor Tuna Şare Ağtürk
https://www.classics.ox.ac.uk/people/prof-tuna-sare-agturk
Faculty of Classics
University of Oxford
Ioannou Centre for Classical and Byzantine Studies
66 St Giles’
Oxford, OX1 3LU
tuna.sareagturk@classics.ox.ac.uk
Research Assistant:
Dr Elifnaz Durusoy-Özmen
https://www.classics.ox.ac.uk/people/dr-elifnaz-durusoy-ozmen#tab-5762691
Faculty of Classics
University of Oxford
Ioannou Centre for Classical and Byzantine Studies
66 St Giles’
Oxford, OX1 3LU
elifnaz.durusoyozmen@classics.ox.ac.uk
Invited Lectures and Presentations:
Tuna Şare Ağtürk, “After Rome, Before Constantinople: The Archaeology of Diocletian’s Capital, Nicomedia.” Oxford Centre for Late Antiquity, Late Roman Seminar, Hilary Term 2026.
Tuna Şare Ağtürk, “The Painted Empire: Rediscovering Colour, Image, and Ideology in Late Roman Nicomedia.” Scuola Normale Superiore and University of Pisa, 18–19 March 2026.
Tuna Şare Ağtürk, “After Rome, Before Constantinople: Urban Transformations in the Late Roman East.” Scuola Normale Superiore and University of Pisa, 18–19 March 2026.
Tuna Şare Ağtürk, “Patterns of Imperial Design: Nicomedia and Decentralized Capitals of the Tetrarchy.” UrbNet lecture series, Exploring Urbanity: Concepts of Centrality and Networks, Aarhus University, Aarhus, May 2025.
Tuna Şare Ağtürk, “Belonging and Transformation: Nicomedia from Roman Capital to Turkish Industrial Center.” Community and Belonging in Roman Asia Minor Workshop, Lady Margaret Hall, Oxford, May 2025.
Tuna Şare Ağtürk, “At the Threshold of Late Antiquity: Diocletian’s Court in Nicomedia.” Invited Talk for the Late Antique Religions et Societies Event Series (LAReS), University of California at Berkeley, Berkeley, May 2025.
Tuna Şare Ağtürk, “Shades of Power: The polychromy of Roman Imperial Power in Nicomedia.” Color Concept / Codici cromatici e architetture dipinte nell’età tardoantica e medievale, Università degli Studi di Firenze, Florence, April 2025.
Tuna Şare Ağtürk, “Recent Excavations in Nicomedia.” Late Antiquity Research Cluster Public Lectures, University of Kent, Canterbury, December 2024.
Tuna Şare Ağtürk, “Nikomedeia: The Grandmother of Constantinople.” International Conference ‘324: Constantine’s Choice and the Origins of New Rome’, held by Istanbul Research Institute in honour of the 1700th anniversary of the foundation of Constantinople, Pera Museum, Istanbul, November 2024.
Tuna Şare Ağtürk, “Recent Discoveries in Nicomedia: New Reliefs and Diocletian’s Hippodrome.” Classical Archaeology Seminar Series, Faculty of Classics, University of Oxford, Oxford, October 2024.
Tuna Şare Ağtürk, “The Colors of Power in Late Roman Anatolia.” International Conference on Pigments, Colors, and Ideas, Bilkent University, Ankara, November 2023.
Tuna Şare Ağtürk, “The Display of Imperial Power in Roman Nicomedia.” ERC RESP Conference: The Roman Emperor Seen from the Provinces, Verona University, Verona, September 2023.
Tuna Şare Ağtürk, “Roman Nicomedia: Recent research and discoveries in the capital of Diocletian.” The Roman Discussion Forum, Faculty of Classics, University of Oxford, Oxford, November 2022.
Tuna Şare Ağtürk, “Tetrarchic Reliefs from Nicomedia: Uncovering the Colorful Life Diocletian’s Capital.” Vortrag für Deutsches Archäologisches Institut, Museum für Abgüsse Klassischer Bildwerke, Munich, February 2020.
Tuna Şare Ağtürk, “Imperial Reliefs of Nicomedia.” Seminar for the School of Classics, University of St. Andrews, St. Andrews, November 2020.
Tuna Şare Ağtürk, “Uncovering an Imperial Complex in Nicomedia, Diocletian’s Lost Capital.” Talk for the Byzantine Studies Program, Dumbarton Oaks Research Library and Collection, Washington DC, March 2019.
Tuna Şare Ağtürk, “Painted Reliefs of Nicomedia.” Talk for Zentrum für Altertumswissenschaften, Institut für Klassische Archäologie, Byzantinische Archäologie und Kunstgeschichte, Universität Heidelberg, Heidelberg, November 2019.
Tuna Şare Ağtürk, “New Tetrarchic Reliefs from Nicomedia.” Winckelmann-Festvortrag, Philipps Universität, Marburg, December 2019.
Tuna Şare Ağtürk, “Made Locally Read Globally?: The Origins of Tetrarchic Art in the Light of Newly Discovered Nicomedia Reliefs.” In Material Entanglements in the Ancient Mediterranean and Beyond, Getty Foundation, Connecting Art Histories, Johns Hopkins University and National Hellenic Research Foundation, Athens, October 2018.
Tuna Şare Ağtürk, “A Tetrarchic Cult Complex with Painted Marble Reliefs from Ancient Nicomedia: A Preliminary Report.” Archaeological Institute of America Annual Meeting, Boston, January 2018.
Tuna Şare Ağtürk, “A Diocletianic Cult Complex with Painted Marble Reliefs from Nicomedia.” Lecture for Columbia University Department of Art History and Archaeology and Sakıp Sabancı Center for Turkish Studies, New York, April 2018.
Tuna Şare Ağtürk, “A New Diocletianic Cult Complex with Painted Marble Reliefs from Nicomedia.” Altertumswissenschaftliches Kolloquium, Forschungsstelle Asia Minor at Münster University, Münster, May 2018.
Tuna Şare Ağtürk, “New Tetrarchic Reliefs from Nicomedia.” Seminar talk for the Graduate Group in the Art and Archaeology of the Mediterranean World, University of Pennsylvania, Philadelphia, October 2018.
Tuna Şare Ağtürk, “The Tetrarchic Reliefs from Nikomedia: Uncovering the Colorful Life of Diocletian’s Lost Capital.” Talk for the Standing Committee for Archaeology, Harvard University, Cambridge, October 2018.
Tuna Şare Ağtürk, “Nikomedia Çokrenkli (Polykrom) Roma Rölyeflerinin Üzerindeki Arkeometrik Çalışmaların Ön Bulguları.” The 39th International Symposium of Excavations, Surveys, and Archaeometry, Bursa, May 2017.
Tuna Şare Ağtürk, “Painted Marble Reliefs from Tetrarchic Nicomedia.” Joint Research Seminar for Departments of Archaeology, and Classics and Ancient History, Durham University, Durham, June 201.
Tuna Şare Ağtürk, “New Tetrarchic Reliefs from Nicomedia.” Art and Power, Classical Archaeology Seminar, Oxford University, Ioannou Centre for Classical and Byzantine Studies, Oxford, October 2017.
Tuna Şare Ağtürk and Mark Abbe, “Painted Marble Reliefs from Tetrarchic Nicomedia: A Preliminary Report.” 8th International Round Table on Polychromy in Ancient Sculpture and Architecture, The Louvre Museum, Paris, November 2016.
Academic Events, Seminars and Symposia:
Tuna Şare Ağtürk, organiser, “Classical Archaeology Seminar: Claiming the Past of Anatolia: Archaeology and Practice.” Hilary Term, 19 January–9 March 2026. Weekly Graduate Seminar Series, Faculty of Classics, University of Oxford, supported by the British Academy and the Faculty of Classics.
Tuna Şare Ağtürk and R. R. R. Smith, organisers, “Tetrarchs, Constantine, and Imperial Art, AD 284–337.” Symposium held at the Ioannou Centre for Classical and Byzantine Studies, Faculty of Classics, University of Oxford, 16–17 December 2021.
Tuna Şare Ağtürk, Achim Lichtenberger, Engelbert Winter, and Klaus Zimmermann, organisers, “The Metropolitan Region of Nicaea / Nicomedia from the Severan to Constantine Period.” Symposium held at the Asia Minor Research Centre, Department of Ancient History, Institute of Classical Archaeology and Christian Archaeology, Westfälische Wilhelms-Universität Münster, in collaboration with the Department of Archaeology of ÇOMÜ, 25–27 March 2019.
Upcoming Events:
International Conference: “Decentralised Capitals of the Roman Empire.” Forthcoming.
Publications:
Tuna Şare Ağtürk, “Recent Research in Nicomedia: New Reliefs and the Location of the Hippodrome within the Urban Context.” Journal of Urban Archaeology 12.1, 2025, 19–31.
Tuna Şare Ağtürk, Kayıp Başkent Nikomedia’nın Renkli Rölyefleri. İstanbul: Koç University Press, 2022.
Tuna Şare Ağtürk, The Painted Tetrarchic Reliefs of Nicomedia: Uncovering the Colourful Life of Diocletian’s Forgotten Capital. Turnhout: Brepols, 2021. (Recipient of the Archaeological Institute of America’s 2023 James R. Wiseman Book Award.)
Tuna Şare Ağtürk, “Myth and Eponymy on the Tetrarchic Frieze from Nicomedia.” Journal of Roman Archaeology 33, 2020, 417–431.
Tuna Şare Ağtürk, Achim Lichtenberger, Engelbert Winter, and Klaus Zimmermann, eds. Imperial Residence and Site of Councils: The Metropolitan Region of Nicaea / Nicomedia. Bonn: Verlag Dr. Rudolf Habelt, 2020.
Tuna Şare Ağtürk, “The Self-Image of a New Imperial Capital City on the Tetrarchic Reliefs of Nicomedia,” in Imperial Residence and Site of Councils: The Metropolitan Region of Nicaea / Nicomedia, edited by Achim Lichtenberger, Tuna Şare Ağtürk, Engelbert Winter, and Klaus Zimmermann, AMS 96. Bonn: Verlag Dr. Rudolf Habelt, 2020, 107–116.
Tuna Şare Ağtürk, “Return of the Emperor: Technical and Iconographic Analysis of the Stolen Emperor Relief from the Nicomedia Frieze.” TÜBAKED 22, 2020, 10–19.
Tuna Şare Ağtürk, “A New Statue of a Weary Herakles from Nicomedia.” Arkeoloji ve Sanat 165, 2020, 63–70.
Mark Abbe and Tuna Şare Ağtürk, “The New Corpus of Painted Imperial Roman Marble Reliefs from Nicomedia: A Preliminary Report.” Technè 48, 2019, 101–110.
Tuna Şare Ağtürk, “A New Tetrarchic Relief from Nicomedia: Embracing Emperors.” American Journal of Archaeology 122, 2018, 411–426.
Tuna Şare Ağtürk, “Nicomedia Çokrenkli (Polykrom) Roma Rölyeflerinin Üzerindeki Arkeometri Çalışmalarının Ön Bulguları,” in Proceedings of the Turkish Ministry of Culture 39th International Symposium of Excavations, Surveys, and Archaeometry, edited by C. Keskin. Kültür Varlıkları ve Müzeler Genel Müdürlüğü, 2018, 293–305.
Tuna Şare Ağtürk, “İmparatorluk Başkenti Nicomedia’nın Renkli İhtişamı: Çukurbağ Kurtarma Kazılarında Ortaya Çıkarılan Görkemli Roma Anıtı,” in Proceedings of the III. International Symposium on History of Kocaeli, edited by H. Selvi et al. Kocaeli Belediyesi, 2017, 343–358.
Submitted and In Preparation
Submitted
Tuna Şare Ağtürk, “Belonging and Transformation: Nicomedia from Roman Capital to Turkish Industrial Centre,” in Community and Belonging in Roman Asia Minor, edited by Christina Kuhn and Marcus Chin. Oxford University, forthcoming.
Tuna Şare Ağtürk, “Nicomedia: The Grandmother of Constantinople in 324: Constantine’s Choice and the Origins of New Rome,” edited by Paul Magdalino and Brigitte Pitarakis. Symposium Series, Istanbul Research Institute, forthcoming.
Tuna Şare Ağtürk, “Shades of Power: The Polychromy of Roman Imperial Sculpture in Nicomedia,” in Color Concept, edited by Elisabetta Neri and Paolo Liverani. Archaeopress Archaeology Series, open access and print, forthcoming.
In Preparation
Further ARCON-related publications are in preparation on Nicomedia and Tetrarchic Centres, the Dardanos Tumulus and wider archaeological material from ancient Anatolia. These planned studies address the integrated spatial reconstruction of Nicomedia through legacy and archival data; the Dardanos Tumulus and its associated finds, and broader themes including Late Roman urban archaeology, ancient Mediterranean visual culture, sculptural polychromy, post-disaster archaeological landscapes, digital spatial modelling, water systems and the methodological challenges of reconnecting dispersed evidence with its urban, material and environmental contexts.
Media, Interviews and Public Engagement:
Documentary Contributions and Podcasts
Tuna Şare Ağtürk contributed to the ARTE documentary Konstantin der Große: Auf Entdeckungsreise in Europa, released by ARTE in May 2026.
https://www.youtube.com/watch?v=wYk_4eI8kgI
Tuna Şare Ağtürk contributed to the educational documentary/podcast for NEOSKOLA, 36 video lessons on the history of Classical Art.
https://www.neoskola.com/egitimler/antik-cagdan-19-yuzyila-sanat-tarihi
Tuna Şare Ağtürk contributed to the educational documentary/podcast for NEOSKOLA, 9 video lessons on the Seven Wonders of the Ancient World. https://www.neoskola.com/egitimler/antik-dunyanin-yedi-harikasi
Interviews and Public Features
Tuna Şare Ağtürk, interviewed by Colleen Walsh for the Harvard Gazette, “Radcliffe fellow heads a team helping preserve the ancient city of Nicomedia in modern-day Turkey,” June 2019.
https://news.harvard.edu/gazette/story/2019/06/radcliffe-fellow-heads-team-helping-preserve-ancient-roman-city-of-nicomedia/
Tuna Şare Ağtürk, interviewed by Nicholas Constans for Dans les pas des archéologues, “Le Baiser des deux Empereurs,” August 2018.
https://nicolas-constans.net/2018-08-19-le-baiser-des-deux-empereurs/
Further ARCON project outputs, including documentary videos, digital resources and public engagement materials, will be added as the project develops.
