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.
Gallic Wars
The following year, 56 BC, Caesar turned his attention to the tribes of the Atlantic seaboard, notably the Veneti tribe in Armorica (modern Brittany), who had assembled a confederacy of anti-Roman tribes. The Veneti were a seafaring people and had built a sailing fleet in the Gulf of Morbihan, requiring the Romans to build galleys and undertake an unconventional land and sea campaign. Eventually Caesar was able to subdue these tribes after a protracted land and sea campaign.