The archaeological remains show that Sarzana was inhabited from the Neolithic period onwards, but the early history of the city is virtually unknown, and there are few sources of information.
Sarzana is first mentioned in a document of 965 by Emperor Otto III (980-1002), in which the “Castrum Sarzanae”, located where now stands the fortress of “Sarzanello”, was recognized as a possession of the Bishop of Luni; at this time Sarzana was mentioned as a simple castle, called the “Castrum de Sarzana”.
We also know that by the end of 13th century, it appeared as a walled village which included an ancient tower.
In another document dating from 1165, Emperor Frederick I (1122-1190) put the city under his special protection, removing it from the domain of the bishops of Luni, to which it was had long been subjected.
With the decline of Luni, Pope Innocent III (1160 approx.-1216) decreed a bishopric in Sarzana. After several changes of ownership between the bishops and the Marquis of Genoa, in 1316 Bishop Gherardino Malaspina (died 1321) appointed Castruccio Castracani (1281-1328) to be Viscount of the Sarzana Diocese, who dominated the city until his death.
After the return of the Pisani, Sarzana came under the domination of the Republic of Genoa (1438) and then to the Medici, who besieged the city in 1487, destroying the “Firmafede” fortress. This fortress was later rebuilt and actually called the Citadel.
Control of the area then returned to the Genoese, who governed the city until the conquest by Napoleon. In 1797 he entered Sarzana in the Ligurian Democratic Republic, naming it the capital of one of the three cantons of the Department of the Apennines.
In 1815, after the Congress of Vienna, its territory was included in the Kingdom of Sardinia, and from 1861 it became part of the Kingdom of Italy.