The Tishreen movement, the anti-regime mobilization of Iraqi youth since 2019, demonstrates many parallels with youth-led protests in other parts of the Arab region, including the shared grievances of corruption and the failed social contract along with demands for radical political change. Yet, one distinctive feature in the Iraqi case is the geographic dimension of protest. The Tishreen movement has been largely localized in Baghdad and central and southern regions, with less adhesion among youth in northern Sunni areas. The article argues that this geographic distinctiveness is reflective of the different political subjectivities and fields of action of youth that have emerged since the 2014 conflict with ISIS and the fragmentation of the political order. The article draws on the concept of the social imaginary, building on the work of Castoriadis and Taylor, to explore how Iraqi youth comprehend themselves as a social category, their relations with other generations, and their imagined parameters of action. The article finds that the conflict’s disruption to the governance of youth, and in particular the institutional mechanisms that mediate their citizenship and security, alongside the profound disruption to their own youthhoods, has transformed their relationship to the central state. It has also changed how they perceive themselves as youth/Iraqi youth, which has led to the emergence of new social imaginaries that demonstrate a rupture among youth along geographic lines. Whereas young people in northern regions are reinventing a notion of youthhood as individualist project focused on personal development and detached from projects of state-building and normative expectations, youth in central and southern regions have instead adopted a new generational conceptualization of themselves, inscribed in nationalist ambitions for a reimagined Iraqi nation-state. These different social imaginaries inform diverging mobilization dynamics and fields of action, divided between the private/personal and the public/national. The article contributes to broader discussions about Arab youth and contentious politics by placing centrally the role of social imaginaries of youth/youthhood as held by young people themselves. More precisely, the article shows how their own shared understandings of what it means to be young, and how they fit into Iraqi society, inform political subjectivities and mobilization dynamics beyond political and socioeconomic grievances. The article draws on 75 semi-structured interviews with youth gathered in Mosul and Basra in 2019-2020 and two round table discussions with Iraqi youth activists held in Erbil and virtually in 2021.