Introduction

International humanitarian law, a relatively modern term, is now used to refer to the principal body of law which governs the conduct of armed conflict: the former phrase, the ‘laws of war’, implied a much more inter-state focus. International regulation of the conduct of inter-state war dates to the mid-nineteenth century. Similarly, international regulation of civil strife began with practice in the mid-nineteenth century.

In international armed conflict, rules which limit the conduct of armed forces have the potential to engage individuals in the international legal system. In internal armed conflict, the extension of belligerent rights and obligations to armed opposition groups effectively engages individuals. This chapter surveys the development of international humanitarian law with respect to individuals in both spheres. The extent to which individuals have been engaged in the international legal system will be assessed against the orthodox accounts of the international legal system examined in Part I. In recent scholarship it has been suggested that there is convergence in humanitarian law applicable in international and non-international armed conflicts; but in this chapter they are addressed separately for several reasons, including the diversity in the historical development of the applicable rules in each type of conflict.

In the post-1945 period, there has been significant development of individual responsibility for international crimes, including war crimes. Individuals have been held responsible under international law for acts which amount to violations of international humanitarian law.