The paper attempts to comprehend the nexus between identity politics, vigilantism, and citizenship within Islamist groups in Yogyakarta in the post-Suharto era. As numerous studies have revealed, post-Suharto era’s democracy in Indonesia has been marked by the persistence of militias, gangs, vigilantism, and street politics. These groups have largely embraced ethnicity, religion, and localism as their symbolism that represents a community that they claim they are defending. The widespread of identity-based groups that frequently breaking the law and public order have been portrayed either as the emergence of ‘uncivil society’ elements that challenging the state authority and threatening the very foundations of civil society and democratic values (see Beittenger, 2009, Jones, 2015, Hefner, 2016) or as the criminals that defend the political and economic interest of the oligarchic elites (Hadiz, 2003:607). Without rejecting certain degree of fact within these studies, the article suggests that these explanations failed to understand the complexity of such groups and what constitutes their persistence in the local political landscape. This article argues that such groups have exercised a form of citizenship that is characterised by the mobilisation of local support, patronage politics and discourse of localised ‘Islamic populism’. In this regard, it suggests that the prominence of Islamist-vigilante groups in Yogyakarta lies in their role as ‘Twilight institution’ that can channel the citizens into the state institutions not just to negotiating their basic rights such as employment and public service through exploiting violence, patronage, and security business but also to defending their imagined and localised Ummah community. In doing so, it embraces the notions that boundary between state and non-state is far more complex and often blurred; therefore, it will be fruitful to recognize that the state authority should be regarded as mingled result of the exercise of power by a variety of local institutions and the imposition of external institutions rather than a coherent and fixed institution (Migdal, 2004, Lunds, 2006).In making such arguments, the paper takes the role of Islamist groups in Yogyakarta particularly groups that loosely associated with the Development United Party (PPP) such as Gerakan Pemuda Kaaba (Kaaba Youth Movement), Gerakan Anti Maksiat (Anti-Vice Movement), and Laskar Hizbullah (Hizbullah troops) as the exemplar for elucidating the intersection between identity politics, vigilantism, and citizenship in localized political landscape. The primary data was conducted through in-depth interviews as well as participatory observations during 2014-2016.