 Following the five major 1783 Calabrian earthquakes, the Mesima River Valley and the Rosarno plain were said to have sunk nearly a meter creating significant shifts in water flow and the creation of lakes and swamps.This change in the geology and ecology of the area provided for an environment for malaria to breed.The earthquakes and subsequent malaria epidemic resulted in upwards of 50,000 deaths in the region and is said to have halved the population by the start of the 19th Century.