My dissertation investigates the sources of popular opposition to mosques in Spain. I contrast the metropolitan area of Barcelona, where opposition to mosques has been frequent and intense, with that of Madrid, where opposition has occurred in just one city, despite the fact that it hosts the country’s second largest Muslim population and suffered a terrorist attack in 2004. I find that conventional explanations that center on the presence of a strong national identity in Catalonia or growing concerns about Islamic extremism are inadequate for explaining the divergent reactions elicited by mosques in Barcelona and Madrid. Rather, I trace this difference to how mosques have been rendered meaningful within local narratives that connect their presence to broader struggles over urban privilege and public recognition. I place particular emphasis on how local interpretations of mosques have been influenced by the spatial development and social organization of large industrial cities where Muslim immigrants have tended to settle. From this historical vantage point, which uncovers early and significant regional differences in the timing of industrialization, the character of urbanization, and the stratification and resulting spatial distribution of migrant populations in each metropolitan area, I explain why opposition to mosques has been so much greater in Barcelona than Madrid. The findings of my dissertation contribute to existing literature on attitudes and practices toward Muslims and other stigmatized minorities in European and other Western contexts. I highlight the importance of looking at how general stereotypes and prejudices are inflected and invoked in distinct ways, and with varying levels of intensity, depending upon how they interact with more localized struggles over social justice and belonging. My conclusions also speak to broader debates concerning the production of symbolic boundaries and the sources of inter-ethnic conflict in settings undergoing processes of ethnic and religious diversification. Specifically, I illuminate how the configuration of urban space in such settings influences reactions to outsider groups and physical markers of their presence. I also bring attention to how ethnic boundaries are shaped by residents’ narrations of the past and present of their communities in the midst of demographic transformation.Ph.D.SociologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/86482/1/aastor_1.pd