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
The Gauls became better integrated with the Empire with the passage of time. For instance, generals Marcus Antonius Primus and Gnaeus Julius Agricola were both born in Gaul, as were emperors Claudius and Caracalla. Emperor Antoninus Pius also came from a Gaulish family. In the decade following Valerian's capture by the Persians in 260, Postumus established a short-lived Gallic Empire, which included the Iberian Peninsula and Britannia, in addition to Gaul itself. Germanic tribes, the Franks and the Alamanni, entered Gaul at this time. The Gallic Empire ended with Emperor Aurelian's victory at Châlons in 274.