Genocide and crimes against humanity were at first considered an outgrowth of war crimes, the latter being the only category of crime accepted as having an international character before the twentieth century. The international community has for centuries been concerned with the outlawing of certain acts during armed conflict, and exhibited the intention to hold the perpetrators of these acts accountable. The establishment of genocide and crimes against humanity as independent international crimes was a gradual process that spread over several centuries, and history shows that war crimes formed the basis for both these crimes. All three international crimes overlap in many ways: certain acts that amount to crimes against humanity constitute...