At the end of the last glacial period (10,000 BC), the climate became milder;[REF] from approximately 7,000 BC, this part of Western Europe entered the Neolithic era and its inhabitants became sedentary.
Around 390 BC the Gallic chieftain Brennus and his troops made their way to Italy through the Alps, defeated the Romans in the Battle of the Allia, and besieged and ransomed Rome.