“A house divided against itself cannot stand.” Abraham Lincoln’s warning has long symbolized the danger of political communities fractured from within. Yet in the contemporary international system, civil war does more than divide the state — it destabilizes the normative architecture of international order itself.

This advanced seminar examines civil war as both an essentially contested concept and a structural challenge to international law and politics. The designation of a conflict as ‘civil war’, ‘insurgency’, or ‘rebellion’ is never neutral; it carries significant legal and political consequences for recognition, neutrality, foreign enlistment, and intervention. By interrogating the politics of naming internal conflict, the course explores how civil wars blur the boundary between domestic jurisdiction and international concern.

Particular attention is devoted to four interrelated dimensions:
a) the conceptual and legal definition of civil war;
b) the promotion and support of insurgencies by external actors;
c) foreign enlistment, transnational fighters, and private military actors; and
d) the evolving meaning of neutrality and non-intervention in contemporary conflicts.

Drawing on scholarship in international law, political theory, diplomatic history, and international relations — and engaging selected case studies from the nineteenth century to the present — the seminar argues that civil wars function as crucibles in which sovereignty, neutrality, and the international order are continuously renegotiated. Contemporary internationalized civil wars reveal not only internal fragmentation, but broader tensions within the global normative system.

Central to the seminar is a commitment to historical thinking as a discipline of judgment. History is not treated as a catalogue of precedents or analogies, but as a method for understanding how legal concepts, political categories, and normative commitments evolve under pressure. By examining how past actors confronted dilemmas of insurgency, neutrality, and intervention, students cultivate historically informed strategic judgment — an essential skill for navigating the complexity and ambiguity of contemporary international decision-making.

The course is designed for students with interests in international law, international relations, diplomatic history, and global political theory.