The Fanum Voltumnae, or shrine of Voltumna, was the chief sanctuary of the Etruscans: fanum means a sacred place, a much broader notion than a single temple. Numerous sources refer to a league of the “Twelve Peoples” (lucumonies) of Etruria, formed for religious purposes but evidently having some political functions. The Etruscan league of twelve city-states met annually at the Fanum, located in a place chosen as omphalos (sacred navel), the geographical and spiritual centre of the whole Etruscan nation. Each spring political and religious leaders from the cities would meet to discuss military campaigns and civic affairs and pray to their common gods. Chief amongst these was Voltumna (or Veltha), possibly state god of the Etruria.
Roman historian Titus Livius mentioned the Fanum Voltumnae five times in his works and indicated "...apud Volsinios..." as the place where the shrine was located. Modern historians have been looking for the Fanum from at least the 15th century but the exact location of the shrine is still unknown, though it may have been in an area near modern Orvieto, believed by many to be the ancient Volsinii. Livy describes the meetings that took place at the Fanum between Etruscan leaders. Livy refers in particular to a meeting in which two groups applied to assist the city of Veii in a war it was waging. The council's answer was no, because Veio had declared war without first notifying it. Livy also says that Roman merchants who travelled to a huge fair attached to the meeting acted as spies, reporting back on Etruscan affairs to authorities in the city-state of Rome. He was alone in mentioning the god Voltumna, whereas Marcus Terentius Varro indicated a god-prince of Etruria. The Latin elegiac poet Propertius (Assisi, ca 47 BC – Rome, 14 AD) writes of an Etruscan god taken to Rome from Velzna (the town of Orvieto). That the Fanum was somewhere in Central Italy in the area between Orvieto and Viterbo is probable enough, but as Titus Livius has given no clue to its locality, and as no inscriptions have thrown light on the subject, it can be but pure conjecture to assign to it this or that particular site.