Structure of the Roman Army

There are two main types of soldier, a Legionary is a Roman citizen, an Auxiliary is not. Each of them must supply their own equipment and swear an oath of loyalty to the Emperor.

Legionaries join an Infantry unit as part of a group of eight men, known as a Contubernium, who all share sleeping quarters. New soldiers are stuck with "Fatigues" (Dirty Jobs) until they can secure a specialists post.

10 Contubernia form a Century, with it's own standard bearer (Signifer), Commander of the watch (Tesserarius), Second in Command (Optio), and a Centurion, to lead them all. Six Centuries together make up a Cohort.

10 Cohorts, plus a small cavalry unit, the Equites Legionis (120 Riders) make up the biggest Roman Army unit of them all, The Legion. The Legion's Symbol is the Roman Eagle, born aloft by the Aquilifer. Cohorts in a Legion are numbered 1-10.

Cohort 1 is extra large with five double Centuries. It's Centurions are the senior ranking Primi Ordines, with the most senior of them all being Primus Pilus, or "First File".

The Primus Pilus can be promoted to the Praefectus Castrorum (Camp Prefect) who is in charge of the daily running of the Legion. Outranking the Camp Prefect are seven men, 6 Staff Officers (the Tribuni Angusticlavii and Tribuni Laticlavius).

The seventh is the Commander of the entire Legion, the Legatus. Back in Rome he is a member of the Senate, the Empire's 600 person ruling elite.

All together a single Legion was made up of around 6,000 troops, all of whom Roman citizens.

While the Roman Legionaries are the backbone of the Roman Army, the Auxiliaries, or non-citizens, are the Specialists. In the Auxiliary Cohorts, men recruited across the empires us their talents and abilities in the service of Rome.

One particular area of expertise was Horsemanship. there were Cavalry only regiments (The Alae), a few double strength cavalry units, including the one in Britannia (The Alae Petriana) along with some partially mounted Cohorts.

Some Auxiliary Cohorts served as regular Infantry, organized like the Legionary Cohorts, however the similarities stopped at the Cohort level, Auxiliaries are part of no bigger unit, there is no Auxiliary Legion, nor a Legate to command them.

Instead, each Auxiliary Cohort has it's own high ranking commander, the Prefectus Cohortis, who leads these more compact and maneuverable units.

When an Auxiliary soldier has served the Roman Army for 25 years, a great reward awaits. He is granted a plot of land, a pension, and all of the rights of a Roman citizen, shared by his family, and all the generations of his name to follow.

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