Santa Fiora is a comune (municipality) in the Province of Grosseto, in the Italian region of Tuscany, located about 110 kilometres (68 miles) southeast of Florence and about 40 km (25 mi) east of Grosseto. Santa Fiora borders the following municipalities: Abbadia San Salvatore, Arcidosso, Castel del Piano, Castell'Azzara, Piancastagnaio, Roccalbegna, Semproniano. In the Middle Age and during the Modern Era Santa Fiora was the capital of an independent State, the County of Santa Fiora.
Santa Fiora is mentioned for the first time in 890 AD, in a document listing properties of the Abbey of San Salvatore, Sforza Cesarini Archive Rome. By the eleventh century the lords of Santa Fiore were the Aldobrandeschi who, in 1082, started the construction of a castle here (Castello S. Flore) and walled the borgo. The power of the abbey passed by degrees to the Aldobrandeschi conti di San Fire, and in turn to the hegemony in Lower Tuscany of the commune of Siena, which was strong influence on Santa Fiora by the mid fourteenth century, a future already foreseen by Dante: "e vedrai Santafior com' è oscura", "and you shall see how obscure is Santa Fiore" (Purgatorio, canto VI, 111). In 1493, with the marriage of Cecilia Aldobrandeschi and Bosio Sforza, the castello and its town passed to the Sforza. The Sforza of Santa Fiora reached their highest point of power with count Guido Sforza di Santa Fiora, who managed to establish himself as a relative of Pope Paul III Farnese, thereby gaining prestigious political positions for his relatives. Later the family became the Sforza Cesarini, who are still well represented and living in their Roman Palazzo Sforza Cesarini. The sovereign rights of the small state of Santa Fiora were sold to the Grand Duchy of Tuscany under Leopold II though all feudal rights remained to the Family.
The County of Santa Fiora (Italian: Contea di Santa Fiora), also known as State of Santa Fiora (Italian: Stato di Santa Fiora) was a small historical state of southern Tuscany, in central Italy. Together with the county of Sovana, it was one of the two subdivisions into which the possessions of the Aldobrandeschi, then lords of much of southern Tuscany, were split in 1274.
At the moments of its creation it included part of today's province of Grosseto, up to the Isola del Giglio, and Castiglione d'Orcia, in what is now the province of Siena. In the 14th century the Republic of Siena was able to capture Isola del Giglio, Roccastrada, Istia d'Ombrone, Magliano in Toscana, Selvena, Arcidosso and Castiglione d'Orcia, reducing the county to its capital, Castell'Azzara, Semproniano and Scansano.
In 1439, after the marriage of Bosio I Sforza and the last Aldobrandeschi heir, Cecilia, the county was inherited by the Sforza family, who would become ruler of the Duchy of Milan and owned also other possessions in Tuscany and the Marche.