The Legions are the basic fighting units for land battles on the worldmap. The basic legion in the beginning is the Manipular Legion. However once the Marian reform is instituted, then the basic legion becomes the Marian legion.
Each Legion has the following infantry officers: 1 Legatus, 1 Praefectus Castrorum, 1 Praefectus Fabrum, 3 Tribunus Militum, 1 Praefectus Cohortis per Cohort, 1 Centurio per Centuria, 1 Decurio per Contubernia, 1 Aquilifer, 1 Signifer per Centuria, 1 Cornicen. Each Legion has the following cavalry officers: 1 Praefectus Equitum, 1 Praefectus Alae, 2 Decurio Eques.
This is the standard Roman Legion at the beginning. The Legio consists of the following subunits: 3 Maniples, 6 Centuria and 12 contubernia. The rank of Praefectus Cohortis is not available. The cavalry subunit or the Turma consists of 6 men. Total numerical strength of the Legion including attached cavalry is 82 men. The minimal salary cost of a Manipular legion at full numerical strength is 265 times the basic salary of a common soldier.
This reshapes the standard Roman Legion, or the Manipular Legion into the Marian Legion. The Legio consists of the following subunits: 2 Cohortes, 8 Centuria and 16 contubernia. The rank of Praefectus Cohortis is available. The cavalry subunit or the Turma consists of 4 men. Total numerical strength of the Legion including attached cavalry is 102 men. The minimal salary cost of a Marian legion at full numerical strength is 313 times the basic salary of a common soldier.
The basic division of the infantry wing of the legion is the Contubernia. A Contubernia is lead by a Decurio. There are 2 Contubernia in 1 Centuria. A Centuria is lead by a Centurio.
The highest subunit of a Manipular Legion is the Maniple. There are 3 Centuria in 1 Maniple. A Maniple is lead by a Tribunus Militum.
The highest subunit of a Marian Legion is the Cohort. There are 4 Centuria in 1 Cohort. A Cohort is lead by by a Praefectus Cohortis.
So when the Marian reform is implemented the Maniple is replaced by the Cohort.
The numerical strength of a Contubernia is 4 men, that is 3 Milites plus 1 Decurio.
Every Legion consists of both cavalry and infantry. The cavalry wing of a legion is called the Ala. Each Ala consists of 2 Turma, or cavalry squadrons.
The commander of a Legion is usually the Legatus Legionis, but can sometimes be a Consul or a Praetor, or if all of them are a missing a Tribunus Militum. The commander is who has the actual battle command of a Legion. It is he, who fights the barbarians on the battle map.
Commanding Officers
Ranging from high to low, the commanding officers of the legion and it subunits, for the infantry are: Legatu Legionis, Tribununus Militum (Manipular), Praefectus Cohortis (Marian), Centurio and finally Decurio. For the cavalry these are: Praefectus Equitum, Praefectus Alae and Decurio Eques.
Non-commanding Officers
Each legion also has NCO's or Non-Commanding Officers. These NCO's take care of various necessary aspects of the legion, such as advise, logistics, salaries, battlefield signals, camp security and so on. Though they are NCO, that does not mean they do not take part in the actual battle, because these officers will fight just like any other ordinary soldier. From high to low we get: Praefectus Castrorum, Praefectus Fabrum, Tribunus Militum (if a Marian legion), Aquilifer, Signifer, Cornicen.
The Praefectus Castrorum is the camp commander. He is in charge of the camp security and camp construction.
The Praefectus Fabrum is in charge of the camp factories, weapon stores and logistics.
The Tribunus Militum may act as an adviser to the commander of the Legion. If there is no commander, then the first Tribunus Militum may act as a replacement, and after the first, the second and ultimately the third.
The Aquilifer is the standard bearer of the legion.
The Signifer is the standard bearer of a Centuria in the legion.
The Cornicen is the buggler of the legion.
Aside from these NCO's there may also be Optio's in the legion. The Optio is a lieutenant to a Centurio, who is assigned with a certain task and because of their task they get twice the normal pay. How many Optio's a legion has depends on the current needs. There are quite a number of types of Optio's, like: Optio Carceris (in charge of prison), Optio Custodiarum (in charge of guard duty), Optio Fabricae (in charge of a workshop), Optio Navaliorum (in charge of boats), Optio Praetorii (attached to headquarters), Optio Statorum (military police), Optio Tribuni (assistant to a Tribunus Militum), Optio Valetudinarii (in charge of a military hospital), Optio Centurionis (chosen man of the Centurio), Optio Equitum (chosen man of the Praefectus Alae).
Soldiers
The Accensi are raw recruits and do not have any equipment. They are enlisted in the army and can train, but they are not enlisted in any Legion. They can be assigned to a Legion by a commanding officer, once they have the required equipment that fits a certain type of soldier.
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There are 5 types of common infantry soldiers.
To what type a soldier belongs, is determined by the equipment he has.
The common cavalry soldier is the Eques. The cavalry who ride on horseback are twice as fast on the battlefield as infantry, or the foot soldiers.
Auxiliary
The commanding officers may also enlist non-Romans into a Legion, if these are available. Non-Romans enlisted into a legion are called Auxilia. Auxilia are often allied, vassal, or conquered barbarians from the provinces, who enlist in the army in exchange for a salary. While they are sometimes not as strong or as well trained as Romans, they can be useful to fill in any gaps in the Legions, or where there is a shortage of men.
All soldiers and officers (except for the Legatus), whether infantry, cavalry or navy can remain in the army for a maximum of 20 years. After a service of 20 years retirement is mandatory. After a service of 10 years retirement is optional. Soldiers and officers who have served at least 10 years in the military, become veterans. Veterans may be entitled to free land given by the state. Soldiers and officers may also freely retire if their salary has not been paid.
