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.
Marcus Claudius Marcellus
Following the end of the First Punic War, in which Marcellus fought as a soldier, the Gauls of northern Italy declared war on Rome in 225 BC. In the fourth and final year of the war, Marcellus was elected consul with Gnaeus Cornelius Scipio Calvus. The previous consuls had pushed the Insubrians, the primary Gallic tribe involved, all the way up to the Po River. Following such terrible defeats, the Insubrians surrendered, but Marcellus, not yet consul, persuaded the two acting consuls not to accept the terms of peace. As Marcellus and his colleague were ushered into office as the new consuls, the Insubrians mustered 30,000 of their Gallic allies, the Gaesatae, to fight the Romans. Marcellus invaded Insubrian lands up to the Po River, just as the previous consuls had done. From here, the Gauls sent 10,000 men across the Po and attacked Clastidium, a Roman stronghold, to divert the Roman attacks. This battlefield was the stage for Marcellus’ confrontation with the Gallic king, Viridomarus, which cemented his place in history.