At the end of the nineteenth century, Brussels became an economically and culturally dynamic capital, with a vivid cultural scene and a burgeoning literary field. Through the analysis of several themes related to the art world and urban development, we question the cultural emergence of this small city and propose a comprehensive definition of what is a cultural capital, using Brussels as a case study. Our essay concludes by arguing that the nineteenth-century Belgian capital was able to assert itself as an influential laboratory for new art forms, even if always remained in the shadow of Paris.