At the head of these legions, Caesar set out for Gaul.

He was at this time not far from forty years of age.
[Sidenote: His pretexts.] Caesar had no difficulty in finding pretexts for making war upon any of these various nations that he might desire to subdue.

They were, of course, frequently at war with each other, and there were at all times standing topics of controversy and unsettled disputes among them.

Caesar had, therefore, only to draw near to the scene of contention, and then to take sides with one party or the other, it mattered little with which, for the affair almost always resulted, in the end, in his making himself master of both.

The manner, however, in which this sort of operation was performed, can best be illustrated by an example, and we will take for the purpose the case of Ariovistus.
[Sidenote: Ariovistus.] [Sidenote: The Aeduans.] Ariovistus was a German king.