grey zone warfare

Into the Grey: Grey Zone Warfare in Past, Present, and Future

‘Grey Zone Warfare’ has emerged since 2014 as one of the key strategic challenges of the 21st century. The ‘Grey Zone’ lies between peaceful (white) action carried out by a nation and hostile (black) action, which could be seen as an act of war. Hence it can be a nebulous concept. Yet the threat is real. NATO has identified ‘growing global uncertainty, more sophisticated and disruptive cyber and hybrid threats, and exponential technological change’ as significant dangers.

We aim to provide clarity by characterising ‘Grey Zone Warfare’ in order to develop understanding of the present and most likely future of warfare. To do this, we have developed a network to study ‘Grey Zone Warfare’, to classify it and develop case studies. Our audience includes academics, practitioners and policymakers, the media, NGOs, and the public. Our work will help make sense of Grey Zone Warfare and put it into perspective.


Into the Grey: Grey Zone Warfare in Past, Present, and Future began in early 2023 and will continue into 2025. Our first workshop will be in Lancaster in June 2023 followed by workshops in Amsterdam (September 2024), in Rome (late 2024), and will end with an event organised in the UK (2025). It is an interdisciplinary project including scholars from history, law, international relations and philosophy to ensure the project embraces all aspects of Grey Zone Warfare. It is also an international collaboration, built on an existing strategic partnership between the Universities of Lancaster and Amsterdam and includes researchers from Europe, Asia and North America. The project is funded by the Arts and Humanities Research Council and Lancaster University.

The project recognises that Grey Zone Warfare is far from a recent development in conflict, and we argue the perceived dichotomy between “past” and the “present” dominant forms of warfare is a deeply flawed basis for our understanding. The guerrilla during the Peninsular War of the early 19th century, the ‘petites guerres’ that accompanied early modern sieges and the Ottoman Empire’s employment of Barbary Pirates to harass shipping of states it was formally at peace with, can all be characterised as Grey Zone Warfare. Analysis of historic experiences will contribute to future-proofing and enriching debates and policies on the pressing issue of Grey Zone Warfare.


Principal Investigator: Professor Marco Wyss, Professor of International History and Security, Lancaster University

Co-Investigator: Dr Samuël Kruizinga, Senior Lecturer in Contemporary and Military History, University of Amsterdam

Network Members

Associate Professor TSE Wai Kit Wicky, Associate Professor, Chinese University of Hong Kong

Professor David Parrott, Professor of Early Modern History, New College Oxford

Dr Bruno Cardoso Reis, Researcher, Centre of Religious History Studies, Universidade Catolica Portugesa

Professor Gunhild Hoogensen Gjørv, Professor in Critical Peace and Conflict Studies (Security and Geopolitics) and Arctic 5 Chair in Security Studies, UiT The Arctic University of Norway

Professor Sir Hew Strachan, Bishop Wardlaw Professor, University of St Andrews

Professor Donald Stoker, The Eisenhower School for National Security and Resource Strategy

Professor Wim Klinkert, Chair in co-operation with the Netherlands Defence Academy, University of Amsterdam

Dr Collin Koh Swee Lean, Research Fellow, S. Rajaratnam School of International Studies, Singapore

Professor Lise Morje Howard, Professor, Government and SFS, Georgetown University

Dr Lukas Milevski, Assistant Professor, University of Leiden

Dr Chiara Libiseller, Lecturer, University of Leiden

Dr Christophe Paulussen, Senior Researcher & Associate Fellow Rule of Law Responses to Terrorism International Centre for Counter-Terrorism, Asser Institute

Dr Brianna Rosen, Visiting Fellow of Practice, Blavatnik School of Government, University of Oxford

Dr Huw Bennett, Reader in International Relations, Cardiff University

Dr Aleksandra Pomiecko, Lecturer in Modern Russian History, University of St Andrews

Dr Jenny Benham, Reader in Medieval History, Cardiff University

Associate Members

Dr Sarah White, Lecturer in Medieval History, Lancaster University

Professor Isabelle Duijvesteijn, Professor of International Studies and Global History, University of Leiden

A black and white photo of a derailed train and rubble in the foreground.


Principal Investigator: Professor Marco Wyss

Administrator: Amy Stanning BA, AKC, MA