The stereotypical image of Barbaricum was very deeply rooted in the mentality of Roman intellectuals. In their recommendations, authors of military treatises sometimes referred to the stereotypical ethnographic image of the Rome’s opponents. Despite their application of literary topoi, the information given by the authors was largely followed by Roman commanders. At times, military treatises offer basic stereotypes, probably deeply rooted in the collective awareness of Roman intellectuals and military men alike. Notably, these stereotypes could have an impact on the practical aspects of military life.
The approach towards foreign ethnic groups in Roman military treatises was twofold: in the case of regular soldiers, aversion to foreigners had to be stimulated by looking for antagonisms, whether religious or cultural. However, it was done in broad strokes, without indicating any individual national features or referring to topoi from classical literature. The situation was quite different in the sections aimed at military commanders. The strategoi needed the most accurate picture of the enemy, their habits, strengths and weaknesses, ways of fighting and even political organization. This knowledge could be used in the course of fighting, in order to gain an advantage over the opponent. Despite the obvious usefulness of these recommendations for commanders, they were not free from ancient topoi, easy to differentiate from practical guidelines. A soldier had to learn to hate his enemy; a Roman commander had to learn about the enemy, get to know them as well as reasonably possible, so as to achieve victory that much easier. This is an indication that despite clearly identifiable transcultural wars waged by the Empire, the military treatises do not place much emphasis on ethnic aspects.