- Army Under AugustusExercitus duce Augusto

The following information gives the organisation of the Roman Army during the reign of Augustus.

At that time there were 28 legions consisting of approximately 5000 infantrymen and was organised as follows :
 
Legion ( Legio )5000
Cohorts ( 10 Cohortes )500
Centuries ( 6 Centuriae )80 - 100
 
Officers :LegatusLegionary Commander
6 Tribuni MilitumTribunes
60 CenturionesCenturions (recruited from the ranks) in charge of centuries
 
RecruitmentTaken from the citizens
Length of service20 - 25 years
Pay250 - 300 denarii per day
Responsible forRepelling invasions and used in important battles for attack
Retirement benefitsLand or cash bounty
 
Other forces recruited to help the legions were made up of archers, slingers, cavalry and infantry and these were the auxiliaries (auxilia) :
 
Cavalry unit ( Ala )500
Turmae ( 16 Tumae )32
Infantry unit ( Cohors )500
 
Officers :Decurion ( cavalry )Decurio
 
RecruitmentNon-citizens
Length of service25 years
Pay100 denarii per day
Responsible forHelping legions occupation and frontier skirmishing
Retirement benefitsRoman citizenship for himself and his family
 
A special bodyguard unit was set up to act as the Emperor’s personal guard.

This was known as the Pretorian Guard, 3 cohorts of which were based in Rome and 6 in towns nearby.
These were made up as follows :
 
Praetorian Guard ( Praetorium )4500
Cohorts500
 
Officers :Praetorian Prefects2 Praefecti Praetorio
 
RecruitmentCitizens (Italy)
Length of service16 years
Pay1000 denarii per day
Responsible forPreservation of the position and safety of the Emperor
Retirement benefits5000 denarii