Gauls
In 58 BC Julius Caesar launched the Gallic Wars and had conquered the whole of Gaul by 51 BC. He noted that the Gauls (Celtae) were one of the three primary peoples in the area, along with the Aquitanians and the Belgae. Caesar's motivation for the invasion seems to have been his need for gold to pay off his debts and for a successful military expedition to boost his political career. The people of Gaul could provide him with both. So much gold was looted from Gaul that after the war the price of gold fell by as much as 20%. While they were militarily just as brave as the Romans, the internal division between the Gallic tribes guaranteed an easy victory for Caesar, and Vercingetorix's attempt to unite the Gauls against Roman invasion came too late. After the annexation of Gaul a mixed Gallo-Roman culture began to emerge.
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.