 When the Grand Duchy of Tuscany rose to power, San Casciano lost its military and strategic role and its history followed that of Tuscany.In 1893, after the annexation of the Grand Duchy of Tuscany to the Kingdom of Italy, a steam-engine railroad was built to link San Casciano and Florence.On 26 July 1944, during World War II, San Casciano was almost entirely destroyed by an Allied bombardment.