Since the Middle Ages, European cities had been centers of government, culture, and large-scale commerce. They had also been congested, dirty, and unhealthy. Beginning in the early nineteenth century, the Industrial Revolution took these unfortunate realities of urban life to unprecedented levels. While historians may debate whether the overall social impact of industrialization was generally positive or negative, there is little doubt that rapid urban growth worsened long-standing overcrowding, pollution, and unhealthy living conditions. Taming the city posed a frightening challenge for society. Only the full-scale efforts of government leaders, city planners, reformers, scientists, and civic-minded citizens would ameliorate the ferocious savagery of the industrial metropolis.