In his book he appears to use slavery as a form of punishment, yet Rome has a record of a large usage of slaves for labor as well as entertainment. Not only this, but he also never mentioned spoils of war or booty obtained by the army, which history shows, is a driving factor in an armies desire for victory. This leads me to believe that Caesar wanted to distort future historians view on his and his soldiers aspirations during the war making Roman's appear fairer and just, which leads me to his second interest. Caesar wanted to secure Rome's place as the great ruling empire of the west and achieve renown among its neighbors. When the Helvetti first attempted to migrate, they attempted to cross the Roman Province with fortifications already in place by Caesar. They tried to sneak past the Romans using the cover of night, clearly not respecting the voice of Caesar or the power of the Legions. Caesar likely thought that the Helvetti undermined the power of Rome, and it was likely the other tribes of Gaul did as well, especially with recent battles involving Spartacus. This also shows with Caesar's first expeditions into Germany and Britain. Some reasoning used in these ventures was to "overawe" these countries, even building a bridge across the Rhine to assert Rome's dominance in the region, just to destroy it some weeks later. Lastly, Caesar was interested in boosting his political career. War and politics in Rome went hand-in-hand, great leadership on the battlefield meant great leadership on the homeland. Caesar, feeling the shadow of Alexander the Great, desired to make a name for himself, more than that of another consul of Rome. This underlying desire, a wide influence of provinces and people, and a great army under his control, you would have to be blind not to see Caesar seizing this opportunity. As for continuing the conquest, no reasons were needed as they soon came to present themselves and happened to be more urgent than anything else at the time.
