Tired of the  battles fought in the area at the time between Florence, Lucca and Pisa, the population of nearby villages Vigesimo, Catiana, Paterno and Carpugnana decided to build here a defensive castle,  named Castello di Franco, later changed to  Castelfranco.
The construction of Castello di Franco (later Castelfranco) was motivated by the ongoing battles between Florence, Lucca, and Pisa that were taking place near the villages of Vigesimo, Catiana, Paterno, and Carpugnana.