The Commentarii de Bello Gallico is an exercise in exaggeration, written to give an audience a totally distorted view, which was probably effective because there was so little contrary information to combat it. The fearsome Suevi who have no neighbours for six hundred miles, who don't drink wine for fear of becoming effeminate, who only wear animal skins, and so on, are among many other tribes who are carefully depicted (when the text isn't outright contradicting itself) as being completely at odds with Rome, and requiring domination.

It does talk quite openly about not just what we would consider Roman military victories, but also the raiding and destruction of camps, including the killing of women and children, and sometimes mass suicide, caused by one misfortune or another. These are all, one way or the other, perfectly acceptable for the time, and any underhandedness or duplicity on the part of the Romans is always preceded, of course, by some nefariousness on the part of the barbarians.

Inflating the number of enemy was common, and was done to either heighten the glory of Rome and the Roman force and their commander, or to help explain away defeats. This has a long history of use in Rome.