From 1347 to 1665, the Black Death claimed nearly the lives of 25 million Europeans. Various outbreaks of the disease had plagued Florence since the 1300s. Renaissance poet Francesco Petrarch was convinced that future generations would find the suffering it triggered unconceivable: 'Oh happy posterity, who will not experience such abysmal woe and will look upon our testimony as a fable." The Hospitaller Brothers who adhered to the teachings of Portughese saint, John of God (1495–1550), served plague victims and other people affected by illness in Florence. (Today, members of this order continue to care for the poor and sick in 53 countries worldwide.) In the 1700s, the San Giovanni di Dio Hospital in Florence underwent renovations and incorporated the private home next door, where explorer Amerigo Vespucci was born several centuries earlier. Its atrium, fitted with a magnificent staircase, was created in 1735, around the time that Saint John of God was canonized. The frescos in the vault were painted in part by Vincenzo Meucci, Violante Ferroni's teacher.