The large-scale withdrawal of military forces from urban areas represents one of the most significant drivers of land-use change in post-socialist Central and Eastern Europe. Based on a national database of former military sites in Hungary, this study investigates the changes in the residential population and social environment of these sites as an outcome of brownfield regeneration. The research combines statistical data analysis of occupational status for the census years 2001, 2011, and 2022 with qualitative methods, including semi-structured in-depth interviews conducted across four case study locations in three Hungarian second-tier cities. The findings reveal three active governance configurations producing distinct social trajectories: social exclusion under market dominance, social mix under sustained municipal involvement, and gentrification in a transitional model where the state eventually withdraws. Ultimately, the study concludes that the social outcomes of military brownfield regeneration are primarily determined by the governance dynamic between municipal authorities and private market actors rather than site attributes alone. Consequently, early and sustained municipal engagement remains the key factor for achieving socially balanced regeneration outcomes.