Gaul (Latin Gallia, French Gaule) is the name given by the Romans to the territories where the Celtic Gauls (Latin Galli, French Gaulois) lived, including present France, Belgium, Luxemburg and parts of the Netherlands, Switzerland, Germany on the west bank of the Rhine, and the Po Valley, in present Italy. The ancient limits of Gaul were the Rhine River and the Alps on the east, the Mare Nostrum (Mediterranean Sea), the Po Valley and the Pyrenees on the south, and the Atlantic Ocean on the west and North. Before the Roman conquest by Julius Caesar (58-51 BCE), the name “Gaul” corresponded to a cultural and military area founded on a common religion and federations of peoples who thought they had a common origin. This common origin probably dates back to the 8th century BCE, when migrant groups of the Bronze Age Urnfield culture spread slowly across the area of the future territory of Gaul. About 390 BCE, the Gauls invaded and sacked Rome. In 222 BCE, Cisalpine Gaul (the region between the Alps and the Po Valley) was conquered by the Romans. The best description we know about the pre-Roman Gaul is in the first chapter of the Commentarii de Bello Gallico, of Caius Julius Caesar. It is clearly a Roman point of view of the Gallic realities:
This is a companion discussion topic for the original content at https://www.worldhistory.org/gaul/.