In myriad forms, violence remains a crucial and, arguably, an increasingly dominant form of political practice by a host of actors in the contemporary world. It is thus not surprising that during the past two decades research on various aspects of violence has increased significantly. Historians have long been the central chroniclers of the violent past, but others, especially social scientists, have recently moved into the spotlight with a host of compelling analyses about the origins, dynamics, and effects of violence, including those of riots, pogroms, civil war, and genocide, among others. Today, the story of violent human behavior is one that many scholars seek to tell and explain, and in a host of different ways — from research methodology and scale, to narrative style. Yet regardless of who seeks to tell histories of violence, the question of what drives people to inflict immense pain and large-scale death on others continues to remain a perplexing question in today's world, and thus is one that remains in urgent need of attention from researchers.