According to legend, the Etruscan League of 12 cities (6th century BC) was founded by two Lydian noblemen; Tarchun and his brother Tyrrhenus. Tarchun lent his name to the city of Tarchna, or Roman Tarquinnii and Tyrrhenus gave his name to the Tyrrhenians - the Greek name for the Etruscans.
Although there is no total consensus on which cities were in the league, the following list may be close to the mark: Arretium (Arezzo), Caisra (Caere or modern Cerveteri), Clevsin (Clusium or modern Chiusi), Curtun (modern Cortona, Perusna (Perugia), Fufluna or Pupluna (Populonia), Veii, Tarchna (Tarquinii or modern Tarquinia-Corneto), Vetluna (Vetulonia), Felathri (Volaterrae or modern Volterra), Velzna (Volsinii or modern day Bolsena), and Velch (Vulci or modern day Volci). Some modern authors include Rusellae.
The league was mostly an economic and religious league, or a loose confederation, similar to the contemporaneous league Greek states. Later, when Etruria was just one of many regions controlled by Rome, the number of cities in the league increased by three. This is noted on many later Grave stones from the 2nd Century onwards.
According to Livy, the twelve city states met once a year at the Fanum Voltumnae at Volsinii, where a leader was chosen.
As well as the "dodecapoli" of Etruria itself, there were two other Etruscan leagues, that of Campania, the main city of which was Capua, and the Po Valley City States in the North, which included Spina and Adria (Atria).
Some authors believe that the number 12 is of ritual significance, and that it is also associated with the supposed Eastern origins of the Etruscan civilisation. Ionia, with whom Etruria had a long association, also consisted of a league of 12 city-states. There is a considerable variation in the spelling of some of the names, depending on the sources, much of it stemming from spelling differences between the various cities, grammatical cases, etc., as well as the national origins and languages of modern investigators. In some cases, we can only guess at the original Etruscan name.
There is an interactive map on the Internet, which links to brief information pages on the individual cities of the League, at http://members.tripod.com/~Centime/Etruscans/cities.html .
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