Scholarship on post-conflict statebuilding, whether as an outcome of revolution, civil war, or externally-induced regime change, underscores the import of designing parallel peacebuilding institutions to accommodate a country’s democratization pathway. Often conducted under the auspices of international and multilateral organizations, international peacebuilding has been shown to reduce the outbreak of violence and civil wars by fostering cross-communal and locally-tailored conflict resolution strategies aimed at de-escalating and depoliticizing group grievances in multiethnic states undergoing transitions from authoritarian rule. This article examines incongruent statebuilding in Iraq by examining the effects of the de-Baathification commission on Iraq’s post-2003 governing trajectory in the absence of international and multilateral support for post-conflict peacebuilding. I posit that the comprehensive purging of former Ba’athists and the institutionalization of de-Baathification bereft of parallel peacebuilding institutions created a legal and structural mechanism for excluding targeted segments of the Iraqi population, which contributed to the re-ethnification of the governing playing-field and radicalization of Sunni-Arab grievances. By triangulating findings from elite interviews of former rank and file members of the de-Baathification Commission, American military, intelligence, and foreign policy elites as well as data mining of WikiLeaks documents pertaining to de-Baathification, I demonstrate that early warning signs regarding the politicization and potential pitfalls of the Commission were ignored in favor of fulfilling an ideologically-driven neoconservative agenda of a post-Ba’athist Iraq that emphasized statebuilding over peacebuilding. I conclude by exploring the ways in which peacebuilding strategies can be adopted to remedy de-Baathification and its outcomes.