Gaul

The Celtic‐speaking peoples who inhabited France and Belgium in Roman times; also their territory. Certain Gauls invaded Italy around 400 BC, sacked Rome 387 BC, and settled between the Alps and the Apennines; this district, known as Cisalpine Gaul, was conquered by Rome in about 225 BC.

The Romans annexed southern Gaul, from the Alps to the Rhone valley in about 120 BC. This became Gallia Narbonensis. The remaining area, from the Atlantic to the Rhine, was invaded and subjugated by Julius Caesar in the Gallic Wars of 58–51 BC. This was later organized into the three imperial provinces: Aquitania in the west, Belgica in the north, and Lugdunensis in the centre and northwest of what is now France.