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.
Gauls
Gaulish or Gallic is the name given to the Celtic language that was spoken in Gaul before the Latin of the late Roman Empire became dominant in Roman Gaul. According to Julius Caesar in his "Commentaries on the Gallic War", it was one of three languages in Gaul, the others being Aquitanian and Belgic. In Gallia Transalpina, a Roman province by the time of Caesar, Latin was the language spoken since at least the previous century. Gaulish is paraphyletically grouped with Celtiberian, Lepontic, and Galatian as Continental Celtic. The Lepontic language and the Galatian language are sometimes considered to be dialects of Gaulish.