The classic tale of epidemiology almost always begins with public health hero John Snow traipsing all over London to track down the source of the 1854 cholera epidemic, ultimately identified as the Broad Street Pump. While Snow’s famous endeavor earned him the title “the father of field epidemiology”, it turns out, as it so often does, that the real story is more complicated. In this bonus episode, we look beyond John Snow to explore the deeper roots of epidemiology with Dr. Jim Downs, Gilder Lehrman-National Endowment for the Humanities Professor of Civil War Era Studies and History at Gettysburg College. Dr. Downs’ latest book, Maladies of Empire: How Colonialism, Slavery, and War Transformed Medicine, reexamines the historical drivers that led physicians to turn their attentions towards the spread of disease in populations. Where does John Snow fit into this revised story of epidemiology? Tune in to find out.