This chapter looks at the history of global health not as an interdisciplinary field of academic study or an aspect of public policy, but rather as the history of health globally.2 What is to be gained from such a massively encompassing perspective? What does the history of health – or rather, the history of threats to health and those health-seeking behaviours meant to restore it – offer researchers and policy analysts who are faced in the most urgent way with present ill-health and future threats of disease? And what, especially, is to be gained from going into ‘deep history’ rather than simply the past decade or century?