‘Pandemics and epidemics’ starts by looking at the conventional picture of the history of plague which divides it into three long pandemics, each of them made up of a series of separate but closely connected epidemics, in particular places, extending over centuries. The ‘Plague of Justinian’, the ‘Black Death’, and the epidemics in India and China in the late 1800s are useful case studies. How do plagues appear and disappear? The European defences against plague in the early modern period included quarantine precautions. Quarantine created protective thresholds which reduced the risk of plague retaining its hold across the whole European mainland.