This book uses data collected in the American journal Morbidity and Mortality Weekly Report for some 350 cities from around the world to look at trends in global mortality at the turn of the twentieth century, a period that witnessed some of the most dramatic changes in city growth on an international scale. The diseases considered are diphtheria, enteric fever, measles, scarlet fever, tuberculosis and whooping cough—as well as death from all causes. The data have never before been systematically analyzed and they give important insights into patterns of mortality from these diseases.