The origins of Susa, "Gate of Italy" fade away in history.
In 500 b.C., when cities like Aosta and Turin had not been founded yet, in Susa there was a Celtic society, perfectly organised by the Druids.
Later on, during the Roman Empire, it reached its maximum splendour.
Then a decaying period followed until the VIII Century when the Franks gave the town new importance and value.
Situated on the ways which linked North Europe to Rome, it was often sacked and set on fire and in the XI Century it was the first land the Maurienne Earls subjected.
It became a Savoy Province and followed up to the end the destiny of this Duchy.
After the Unity of Italy it entered Turin Province.