Legions, alae and cohorts
The Roman Army was a complex entity consisting of many subunits which were restructured and reformed several times throughout the course of history. For example, in Augustan times the Germanic troops were an integral part of the Roman Army, whereas in Caesarian times they were independent and autonomous combat units of allied tribes.
The military units which are described hereafter focus on the time of the Emperor Augustus in order to explain the events of the Varus Battle. The characterised military units are the ones which were stationed in Germania under Varus’ command and which occur repeatedly in descriptions.