List of Roman auxiliary regiments

This article lists auxilia, non-legionary auxiliary regiments of the imperial Roman army, attested in the epigraphic record, by Roman province of deployment during the reign of emperor Hadrian (r. 117–138 CE).

The index of regimental names explains the origin of the names, most of which are based on the names of the subject tribes or cities of the empire where they were originally recruited. (As time went by, they became staffed by recruits from anywhere, especially from the province where they were deployed.)

During most of the Principate era, until 212 CE, auxiliary regiments, called auxilia by the Romans, were formations kept separate from the legions, who were recruited from Roman citizens only. Auxilia were mostly recruited from the peregrini, the vast majority of subjects in the Roman empire who did not hold Roman citizenship. (in 212 CE, all the inhabitants of the empire were granted Roman citizenship).

There were three basic types of auxiliary regiment:

A number of regiments, of all three types, were designated sagittariorum (sagitt), indicating that their members were equipped as archers. After about 80 CE, about 12 percent of regiments were enlarged from the quingenarie size and designated milliarie, which nominally consisted of 1000 soldiers, but in reality consisted of 720 soldiers, 800 soldiers, and 1040 soldiers respectively.

Table I below lists auxiliary regiments during Hadrian's rule, for which there is the most comprehensive evidence. The table does not show regiments that were attested to in the 1st century but that, according to Holder, were dissolved by 117 CE, nor those that were probably founded after 138 CE. The precise number of regiments that existed during Hadrian's rule is disputed. The regiments are listed by the Roman province where they were deployed c. 130 CE.

The rule of the first emperor, Augustus, (30 BCE–14 CE) saw the foundation of the majority of the regiments attested in Hadrian's time. In the earlier part of this period, regiments were raised from and named after individual tribes, for example Campagonum, Trevirorum and Bessorum. Later, units were raised from and named after broad national groups, for example Hispanorum, Gallorum, and Thracum.

...
Wikipedia