Using data collected for 350 cities from around the world, the authors use a variety of analytical methods to provide a global picture of what was happening to infectious epidemic diseases at a critical period in urban evolution on the international stage. The diseases considered are diphtheria, enteric fever, measles, scarlet fever, tuberculosis, and whooping cough. To place the results in a wider time context, other data are used to look both backwards and forwards for nearly a century on either side of the twenty-five-year time window. The book presents a number of results that may be interpreted in the context of debates on the causes of long-term mortality decline from these infectious diseases. It will be of interest to students of demography, history of medicine, and economic history as well as to researchers already active in these fields.