The origin of the square goes back to the thirteenth century, when the area was owned by the Uberti Family, at the time the most powerful family in Florence. The Uberti supported the Ghibellines (a pro-imperial faction) while their main opponents, the Buondelmonti family, supported the Guelphs (a pro-papal faction). The two parties tried to gain control for centuries, with the Ghibellines gaining the upper hand. In 1266 however, after the defeat of the imperial army at the Battle of Benevento, the Guelphs expelled the Uberti family and all their properties were razed. As a symbol of victory, the rubble was not cleared for more than a decade, after which it became an open square. The Palazzo Vecchio and adjoining Uffizi were also built on the former property of the Uberti Family.