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.
Julius Caesar
Though the Gallic tribes were just as strong as the Romans militarily, the internal division among the Gauls guaranteed an easy victory for Caesar. Vercingetorix's attempt in 52 BC to unite them against Roman invasion came too late. He proved an astute commander, defeating Caesar in several engagements, but Caesar's elaborate siege-works at the Battle of Alesia finally forced his surrender. Despite scattered outbreaks of warfare the following year, Gaul was effectively conquered. Plutarch claimed that during the Gallic Wars the army had fought against three million men (of whom one million died, and another million were enslaved), subjugated 300 tribes, and destroyed 800 cities.