Julius Caesar described the Gallic Wars in his book "Commentarii de Bello Gallico", which is the primary source for the conflict, though modern historians consider it to be unreliable. Caesar makes impossible claims about the number of Gauls killed (over a million), while claiming almost zero Roman casualties. Modern historians believe that Gallic forces were far smaller than the Romans claimed, and that they suffered tens of thousands of casualties. Historian David Henige regards the entire account as clever propaganda meant to boost Caesar's image and suggests it is of minimal historical accuracy. The campaign was still exceptionally brutal and untold numbers of Gauls were killed or enslaved, including large numbers of non-combatants.