As Caesar's army crossed the Alps and into Gaul in the 1st century B.C., they built temples, aqueducts, amphitheatres and roads. Along those roads, Rome's army planted the vine. There is still evidence today in Brouilly and Morgon of those Roman vineyards. After Rome left, the area was invaded by the Barbarians and then the Arabs who also tended the vines and enjoyed the fruits thereof. Founded in the 10th century by the powerful nobility that created the principality, the town of Beaujeu in the western hills of Beaujolais, gives the region its name. It was ruled by the Dukes of Beaujeu until it was ceded to the Bourbonnais in 1400.