“Auxiliary” refers to non-citizen soldiers, recruited from peoples allied with or subjugated by the Romans. They played a vital role in the Roman military by supporting the legions. Auxiliaries were important throughout the battles described in Tacitus’s work, especially during the Batavian revolt, in which many left the army to join Julius Civilis.

“Caesar” and “Augustus” were Roman titles, the former of which was based off the dictator Julius Caesar and the latter a title given to Octavian (the first Roman emperor), meaning “revered.” The title “Augustus” was subsequently used to denote a Roman emperor, while “Caesar” was a junior rank given to heirs.

The cursus honorum, meaning “course of honors” in Latin, was the Roman term for the sequential order of public offices held by aspiring politicians in Rome. Men of the Senatorial rank had a set career path, in which they would serve in the military for roughly 10 years as a young man and then become a Questor (a public official with varied responsibilities), an Aedile, and so on until they reached higher ranks such as consuls. During the Principate, the cursus honorum underwent changes as power was concentrated in the hands of the emperor, removing the responsibilities of some roles and making imperial favor important in success.