Rome’s powerful military was made up of legions recruited throughout its empire, but the large portion of auxiliary troops is widely overlooked. Auxilia were the reserves for the Roman Army, made up of non-citizens who did not enjoy full legal rights as a regular Roman. After 25 years of service, however, the soldier was granted citizenship and left the army. The auxiliary were formed under the reign of the first emperor, Augustus. The auxilia were formed into cohorts of 480 men and were named by their region of recruitment. There were three types of “regiments” in the auxilia:
Alae were made of only cavalry
Cohortes peditatae were simply foot soldiers
Cohortes equitatae were a mix of infantry and cavalry and numbered 600 troops instead of the regular 480. There would be 480 infantry and around 120 cavalry
Huge amounts of soldiers were recruited for the auxiliary during the reign of Augustus because of the large expansion of the empire. The majority of auxilia came from Gaul, or modern day France. By the reign of Hadrian, the number of auxiliary troops was nearly double that of the regular legionnaires. Hadrian recruited from Germany, England, the Balkans, Switzerland, the Danube, the Middle East, Egypt, and North Africa. Troops were not required to speak Latin, and many chose to retain their native languages.
Treatment of the auxilia was much worse than that of the legionaries. A legionnaire was given much better armour than an auxiliary, who mostly received chain mail, lamellar armour, or no protection at all. A regular legionnaire was paid 255 denarii each year while an auxiliary was given only 188. Even a tesserarius (equivalent to a corporal) did not make as much as a regular legionary.
Many of the auxilia were deployed to border provinces or areas in conflict. They were the prime fighting force in the Batavian revolt and the Illyrian revolt. They were also an important part of Trajan’s Dacian Wars in modern-day Romania. Though not as revered as the legions, Rome’s auxiliaries were still a key component of their empire’s success.