Farnese is on the border with Tuscany and in its territory have been found settlements from the Bronze Age. In the twelfth and tenth centuries BC, the tufa plateau on which the village stands today, were surrounded by two gullies that had dug steep walls, and was inhabited by the Falisci. Proof of this is an area of ​​extensive tombs of 12 hectares relating to the period 2500-1900 BC.

In the Roman period, from the Republic to the Imperial age, there are numerous rustic villas connected by a capillary system of the original roads. Many tracks are located within the Selva del Lamone.

From the tenth century began the phenomenon of people seeking shelter on fortified plateaus from the invasions. Among these castles also was Castrum Farneti, which owes its name to an oak called ‘farnia’.

Farnese was one of the possessions of Orvieto and here begins the gradual emergence of the family from which they took their name.

In this period the Farnese were brave leaders, good diplomats, and were vassals to the service of the City of Orvieto. They were associated with the armies of the Church to defend the territories usurped by various Ghibelline families. Their activity has been documented since the late thirteenth century. Towards the end of the thirteenth century the village came to the Farnese family who kept it until 1649.

The town began to grow and the period of splendour culminated with the Duchy of Castro, created by Pope Paul III Farnese, for his son Pier Luigi.

After the destruction of Castro at the behest of Pope Innocent X, Farnese became part of the Diocese of Acquapendente. Because of the enormous debts to maintain the splendour of the Farnese court in the Duchy of Parma and Piacenza, the village was sold on June 7, 1658 to Cardinal Flaminio Chigi, nephew of Pope Alexander VII, for the high sum of 275,000 scudi.

The purchase goal was to get a title for the wealthy family of bankers. Thus was born the Farnese autonomous Principality that would last until 1825. Agostino Chigi, Prince Farnese, issued an additional statute and built the Ceccarini-Chigi palace, which now houses the Town Hall.