Dr Henning Tamm

Dr Henning Tamm


Researcher profile

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Dr Henning Tamm joined the School of International Relations in September 2016. Previously, he was a Postdoctoral Prize Research Fellow at Nuffield College, University of Oxford, and a Predoctoral Fellow with the Program on Order, Conflict, and Violence at Yale University’s MacMillan Center for International and Area Studies. He received his DPhil (PhD) from the University of Oxford.



  • Armed Conflict in Africa (IR3070)
  • Rebels, Terrorists, Militias: The Comparative Analysis of Armed Groups (IR4563)
  • International Security (IR5001)


  • Foreign Policy and Diplomacy in Global Politics (IR1006): lectures on African Foreign Policies (Nigeria and Rwanda)
  • Issues in International Relations (IR2006): lectures on Waging War
  • Honours Dissertation (IR4099): lecture on Case Studies and Comparative Case Study Methods

Research areas

One of Dr Tamm's main research interests concerns state support for rebel groups. His International Security article on the Congo Wars argues that rulers in post–Cold War Africa often form alliances with rebel groups abroad to alleviate threats to their political survival at home. Going beyond this article in terms of both time period and theoretical focus, his ongoing book project, "Revolutionary Sponsors," investigates African revolutionary leaders and their support for rebel groups since independence. The research he conducted in the Democratic Republic of Congo (DRC), Rwanda, and Uganda also resulted in an African Affairs article on status competition and the direct interstate clashes between Rwanda and Uganda in the DRC.

Together with Allard Duursma (ETH Zürich), he has been working on several papers on mutual interventions, that is, rival states simultaneously intervening in each other’s intrastate conflicts by supporting rebel groups. Their International Studies Quarterly research note develops this concept and introduces their data on Africa (1960–2010). It conceptualizes mutual interventions as a distinct, indirect form of interstate conflict and shows that they are more common and last much longer than direct interstate conflicts in Africa. Their European Journal of International Relations article explains why some mutual interventions end in bilateral negotiated settlements whereas others end due to events in, or actions by, only one of the two states. In their contribution to an International Studies Review forum, they discuss why negotiated settlements of mutual interventions rarely lead to the resolution of the associated intrastate conflicts.

Dr Tamm's other major research interest is rebel group fragmentation. His International Studies Quarterly article develops a theory that explains how state sponsors foster either cohesion, fragmentation, or internal coups. It illustrates the theory with case studies of Sudanese and Lebanese insurgent groups. His forthcoming Journal of Strategic Studies article elaborates on this theory and dissects how external troop support affected rebel fragmentation in the Second Congo War. While these articles primarily ask why some groups split whereas others remain cohesive, his project on “Varieties of Insurgent Fragmentation” examines how groups split. The project received funding from the Carnegie Trust.

PhD supervision

  • Thomas Hinkel
  • Muhyadin Abdillahi Saed

Selected publications


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