As far back as 2900 BC, the site of a megalithic settlement, the city of Aosta was the military centre of the population of Salassi. When the latter were defeated by the Roman troops during the empire of Augustus, the city became a military settlement, was named Augusta Praetoria, and quickly grew both in importance and prosperity.
Called the Rome of the Alps, it suffered numerous invasions by the Burgundies, Ostrogothians, Byzantines and Franks. In the 10th century, it belonged to the king of Burgundy who, in 1025, handed it over to Umberto Biancamano. Whether under the control of the Savoy family or under the Italian state, the Valle d'Aosta has always enjoyed significant political autonomy, confirmed in 1948 by the promulgation of the special Statute.