Following the 2003 US-led invasion of Iraq, broad consensus surrounded the notion that political violence and civil war had been largely driven by ethnic and religious antagonisms. Yet, in global terms, recent literature provides evidence that the civil wars that proliferated at the end of the Cold War era are better explained by conditions that favor insurgency rather than ethnic or religious characteristics. In attempting to understand post-invasion violence in Iraq, particularly in the years 2004 – 2007, this paper builds upon two prominent strands of research. First, I evaluate recent literature that explores the conditions under which ethnic, religious, and cultural cleavages become politically salient. Second, within the context of Iraq, I examine the ways in which political factors associated with weak states and instability—including poverty, large populations, displaced persons, and additional human development indicators—contribute to rebel recruitment. Relying upon the theoretical and empirical claims of past approaches, this paper considers the linkages between levels of violence and the US-led political transition process. Particularly, this research focuses on the connection between levels of violence, dissatisfaction among Iraq’s diverse ethnic, religious, and sectarian groups, and emerging realms of political contest. In assessing the volatility of Iraqi society during periods of political transition, this analysis reveals the impact and importance of the US-directed political transition process, including efforts to: (a) establish an Iraqi Interim Government and hold elections; (b) structure security policy; (c) influence the development of the Iraqi constitution; and (d) integrate or isolate key religious and political leaders into the emerging political system. Upon a critical examination of the above factors, this study argues that the inability of the United States and Coalition partners to quickly and effectively implement an inclusive political transition process increased the probability of violence and instability throughout Iraq. Moreover, rather than overemphasizing the ethnic and religious dynamics of post-2003 violence in Iraq, conflict is more accurately understood through political competition and conditions that favor insurgency.