Ariovistus had already conquered much of eastern Gallic territory only a few years prior, but Caesar was able to reverse the situation through diplomacy.
Ariovistus was named a friend and ally of the Roman people, but this relationship proved to be short lived.
Ariovistus it seems, viewed this part of Gaul as his territory, and Caesar's presence was considered a violation of their treaty.
Moreover, Ariovistus, for his part, had assumed to himself such pride and arrogance, that he was felt to be quite insufferable.
Perceiving that Ariovistus kept himself in camp, Caesar, that he might not any longer be cut off from provisions, chose a convenient position for a camp beyond that place in which the Germans had encamped, at about 600 paces from them, and having drawn up his army in three lines, marched to that place.
Thither Ariovistus sent light troops, about 16,000 men in number, with all his cavalry; which forces were to intimidate our men, and hinder them in their fortification.