Celtic warfare
The "Gallic Wars" were a series of military campaigns waged by the Roman proconsul Julius Caesar against Gallic tribes, lasting from 58 BC to 51 BC. The Romans would also raid Britannia and Germania, but these expeditions never developed into full-scale invasions. The Gallic Wars culminated in the decisive Battle of Alesia in 52 BC, in which a complete Roman victory resulted in the expansion of the Roman Republic over the whole of Gaul. The wars paved the way for Caesar to become the sole ruler of the Roman Republic.
History of France
Over the course of the 1st millennium BC the Greeks, Romans and Carthaginians established colonies on the Mediterranean coast and the offshore islands. The Roman Republic annexed southern Gaul as the province of Gallia Narbonensis in the late 2nd century BC, and Roman forces under Julius Caesar conquered the rest of Gaul in the Gallic Wars of 58–51 BC. Afterwards a Gallo-Roman culture emerged and Gaul was increasingly integrated into the Roman Empire.