Killer cities and industrious cities? New data and evidence on 250 years of urban growth.

The article investigates the existence of a demographic penalty—characterized by high mortality and low natural increase—in cities during the Industrial Revolution (IR). Using a novel dataset of nearly 2,000 crude demographic rates from 142 large cities across 35 countries between 1700 and 1950, the study finds that mortality rates actually declined faster than fertility rates during the IR era, leading to increased natural population growth, especially in larger cities. Econometric analyses reject the hypotheses that death rates rose and birth rates fell disproportionately in industrializing cities, suggesting that the negative health impacts of industrial urbanization were outweighed by positive effects from rising incomes, improved nutrition, public health investments, and increased life expectancy. The findings challenge traditional views of "killer cities" and "industrious cities" by showing a declining demographic penalty associated with urbanization during industrialization.