Julia Vassileva

Dr. Julia Vassileva is a Postdoctoral Research Fellow at Harvard Kennedy School’s Belfer Center for Science and International Affairs. Her work lies at the intersection of international security and international law, focusing on how norms are strategically adopted in contexts of great-power competition. This includes work on how international law is used to govern international peace and security, amongst developments of the digital age and changing character of war; how small and “in-between” states navigate grey zones between law and power; and how international law functions as an instrument of strategy and statecraft. She has worked on these topics in Europe, the United States, and Asia. She is also interested in how institutional actors—including women as experts, diplomats, policymakers, or negotiators—shape security governance and norm implementation in practice, with a book on women’s roles in peace processes currently under review at Cambridge University Press.

In 2024–2025, Julia was a visiting scholar at Columbia University in New York while completing her Ph.D. in Politics (International Law and Security Studies) at Tallinn University, Estonia. She also holds degrees in International Relations and Law from the University of Oxford, the University of Vienna, and the College of Europe in Bruges.

In 2021–2022, Julia briefly left academia to work for EU institutions in Brussels, at the European Commission and the EU’s diplomatic service (EEAS)’s Directorate for EU-UN relations. In summer 2022, a few months after the invasion of Ukraine, she relocated to Estonia to begin her field-based doctoral research on dynamics at the EU and NATO frontier with Russia. To gather first-hand data, she undertook visiting research stays throughout 2023–2024 in Georgia, Moldova, Armenia, Azerbaijan, and Turkey. She collaborated with local scholars, civil society, public sector actors, international organizations, and embassies and worked remotely with colleagues in Ukraine.

Alongside her current appointment at Harvard, Julia was recently a researcher at the UN’s International Law Commission in Geneva and New York, a visiting associate professor at Osaka Metropolitan University in Japan, and a visiting researcher at the National University of Singapore’s Center for International Law. She also serves as an independent external legal expert at NATO’s Cyber Defense Center. Her academic work is published in journals by OUP, CUP, and others.