If for Fernand Braudel the central event of the Renaissance is represented by the combination of circumstances which allowed Europe to dominate the seas, Yves Renouard considers the traumatic experience of the Plague, with its heavy toll of victims, as the turning point between the Middle ages and the modern era. As soon as European, and above all “Italian” society realised that the disease had become endemic, it elaborated, at all levels, several measures which confirmed the non-fatalistic character of European culture, and its propensity to brace itself for resistance in a non conjunctural perspective (as well as some environmental concerns). Sometimes the repetitive nature of the outbursts of the Plague caused the disease to take on less marked characteristics, which made it somewhat similar to other lethal endemic diseases, whose common origins were individuated in fast-spreading, “selective” contagion among the poorer urban masses, forced to live in a hygienically degraded environment. If the confidence in the therapeutic efficacy of medicine was limited, this was not true as regards the administrative measures implemented by the health authorities in order to circumscribe contagion, whose modernising influence resulted, as a side effect, in more effective control over the urban population.