Gaul

Ancient Roman name for the land N of the Pyrenees, S and W of the Rhine and W of the Alps. In 900 BC, tribes of Celts began to migrate across the Rhine and spread S. In 222 BC, the Romans conquered the region S of the Alps, calling it Cisalpine Gaul. By 121 BC, Rome captured the area N of the Alps, known as Transalpine Gaul. In the Gallic Wars (58–51 BC), Caesar completed the conquest of Gaul.

World Encyclopedia. Philip's, 2005.