Tuomas Heikkilä, PhD, MAE, is one of the most influential Finnish medievalists. He is currently employed at the University of Helsinki as a Professor of Church History. Previously, he served as the Director of the Finnish research institute in Rome, Italy (2013-2017), a Visiting Research Fellow at the Swedish Collegium for Advanced Study (2010), and a Visiting Scholar at the University of Gothenburg (2009).

Originally trained as a historian, Heikkilä has emphasized multidisciplinary scholarship and collaboration with scholars in fields such as computer science, evolutionary biology, electron microscopy, radiocarbon dating, and bio-codicology. His areas of expertise encompass medieval written culture, computer-assisted stemmatology, parchment fragments, manuscript studies, medieval hagiography, and monastic history. Heikkilä has extensively published on these topics in multiple languages. Additionally, he has played a central role in creating databases focused on medieval parchment fragments, charters, and codices.

Heikkilä has led several large-scale research projects as the Principal Investigator, focusing on the arrival and evolution of written culture in Finland, the development of computer-assisted methods for textual criticism and stemmatology, the integration of scientific and humanities research approaches in manuscript studies, and medieval calendars.

Heikkilä's almae matres include the University of Helsinki, Eberhard-Karls-Universität Tübingen in Germany, and the Biblioteca Apostolica Vaticana, where he obtained the European Diploma in Medieval Studies. Heikkilä has received numerous awards for his research and holds the titles of docent in general history and church history (University of Helsinki) and docent in Finnish history (University of Turku). Heikkilä is an invited member of esteemed institutions, including the Finnish Academy of Sciences and Letters, Academia Europaea, the European Academy of Humanities, Letters, Law, and Sciences, as well as the Kungliga Samfundet in Sweden.