This chapter focuses on a legalistic foundation, utilizing the definitions presented in the 1948 Genocide Convention and the 1999 Rome Statute. All genocides are complex events, requiring a high level of organization and utilization of multiple types of resources, and yet, each event is a unique event emerging from its own specific historical moment and situational context. Most genocide events entail multiple modalities; the Convention provides an encompassing set of actions recognizing that the destruction of a group will entail much more than direct homicide events. Fein identified four core casual triggers and contexts of genocide events: ideological, retributive, developmental, and despotic. Developmental, or colonial, genocides are the result of an ‘advanced’ society’s interactions with indigenous groups during territorial and economic expansion. Ideology has a central role in the initiation and perpetration of any genocide event. It frames the mobilization of resources and permeates a national culture, thereby encouraging participation and discouraging intervention.