From the first half of the 15th century onwards, Palermo went through an enormous and impressive economic, demographic and urbanistic development, manifesting a substantial cultural facelift. Though the times were rather difficult due to the frequent incursions of the Turks, and the disastrous effect of epidemics and other diseases, the enthusiasts of the "humanæ litteræ" were great in number. Up to Caxaro's visit to Palermo many native men familiar with the "studia humanitatis" made a name for themselves and for their town, scholars like Giovanni Aurispa and Giovanni Marrasio.