Armies

Legion (6000) is divided into 10 cohorts
Cohorts (600) were divided into 3 maniples
Maniples (200) were divided into 2 centuries
Centuries were 100 men

Several legions were one army

Commander was either the consul, proconsul, praetor
Consul or proconsul- consular armies (2 legions)
Praetor- could only command one legion

Under the consul were the legati (senators)
Under the legati were the tribunes
Under the tribunes were the centurions