Introduction

Since the earliest of times, diseases have shaped the course of human history. Diseases and, in particular, epidemics have affected humans economically, politically and culturally.1 Some diseases have even been credited or blamed for causing the success and failure of societies. The fall of the Roman Empire, for instance, has been attributed to a pandemic of bubonic plague.2 Others argue that malaria was to blame.3 The most obvious effects of disease, indeed, have been demographic: they have caused misery and death and have led to declining or stagnant population numbers.The collection of four articles in this issue focuses on the burden of disease in the Low Countries. Each article deals with a different disease that was typical for a specific era: medieval plague, early modern smallpox, late nineteenth-century tuberculosis and twentieth-century cancer in the form of mesothelioma. The articles stem from a workshop held at Maastricht University as part of what has become an annual WOG event since 2008, the Day of Historical Demography.4 The Ninth Day of Histor ical Demography, which took place in December 2016, was devoted to the study of diseases, causes of death and the epidemiological transition.In the introduction to this special issue we first discuss the main sources and indicators used to examine the burden of disease in the past. Next, we introduce the theory of the epidemiological transition and provide a brief overview of the literature for the Low Countries. Finally, we present the four key diseases in this issue and the new insights their analyses bring.