Intellectual histories of health inequalities and of social epidemiology generally trace the modern “discovery” of health inequalities to the middle of the nineteenth century, when states began collecting sufficiently detailed data on mortality to allow for comparisons of death rates across small geographic areas or groups of individuals with particular occupations (see, e.g., Berkman and Kawachi 2000; Adler and Stewart 2010). In the 1820s and 1830s, Louis-René Villermé studied the link between poverty and mortality at various geographic scales from the street to the département1 in France, and in the 1840s he documented differences in life expectancy among workers in different industries, linking them to differences in lifestyles and working conditions (Julia and Valleron 2011). Rudolph Virchow, a pathologist and representative of the German Progress Party (Deutche Fortschrittspartei) in the Prussian parliament, was working around the same time on the spread of typhus; his 1848 research convinced him that “medicine is a social science and politics is nothing more than medicine on a large scale” (Mackenbach 2009). In 1845, Friedrich Engels, comparing working-class residents of Manchester, England, to their better-off neighbors, identified mechanisms linking socioeconomic status (SES) and health (Engels 1987). These authors and others laid the groundwork for the disciplines of social medicine and social epidemiology, whose central task is understanding how social conditions affect health in the population at large.