The article contributes to the urban studies literature and the study of social movements in divided societies by disclosing the distinctive features and mobilizing potential that the notion of urban commons retains in a war-torn society with a socialist legacy. Specifically, it investigates how urban space and urban commons are reclaimed in a post-conflict and post-socialist country such as Bosnia and Herzegovina. By using Sarajevo as a case study, the article explores several grassroots initiatives undertaken by local urban activists to reappropriate cultural buildings and public space in the city. The study discloses that in a post-conflict and post-socialist society urban commons can bear a unifying potential as acts of commoning favor trust reconstruction processes and strengthen community ties. While the erosion of social ties and the legacy of the war might not encourage mobilization for the commons, the reference to socialist-era practices and language can represent a vantage point to advocate in favor of collective governance. Throughout their actions, urban activists instrumentally referred to the historical experience of socialism to develop a discourse that resonates with the domestic cultural environment. The article points also to a generational difference amongst activists in their references to Yugoslav state socialism. While long-time activists strove to critically reappraise it, the younger ones born in the immediate post-war period appear to hold a more superficial and ambivalent historical knowledge of the socialist heritage, to which they had only partial access and no lived experience.